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YOUR RESEARCHBore scoring on 996 ?
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issue
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It�s only an issue until it happens to you, and yes this particular problem is an issue on these and many other plated cylinder aluminum block engines.
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Suggestion
The biggest problem is that DME acually works as if it were two separate three cylinder engines, bank 1 and bank 2, each bank gets the same injector pulse time, and is checked by first/front 02 Sensor for that bank.
Leading evidence: 'issue' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'issue' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check by first/front 02 sensor' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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This is why we mandate new injectors are fitted on rebuilt engines, along with a new MAF and primary o2 sensors at bare minimum.
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I just received a response from FSI and they said this was an oversight and that the existing injectors will be replaced with new.
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I run 1K miles on the new oil, then dump it, and perform my new UOPA after that oil service has 5000 miles on it.
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I'm sure the oil was ran with the original injectors for majority of its life so it's safe to say that they were not in bad shape.
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Check by first/front 02 sensor
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Suggestion
The biggest problem is that DME acually works as if it were two separate three cylinder engines, bank 1 and bank 2, each bank gets the same injector pulse time, and is checked by first/front 02 Sensor for that bank.
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Suggestion
It is described as a cleaner but also something that adds lubricity to the fueling system and the fuel itself and in turn helping lubricate the upper portion of the cylinders.
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issue
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Reported cause
It�s only an issue until it happens to you, and yes this particular problem is an issue on these and many other plated cylinder aluminum block engines.
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Hi guys.
I'm wondering if the 997 bore scoring issue is a problem on the 996. I initially thought it was a 997 problem only but I'v been reading all sort of things and I don't know what to think about this pretty scary issue.
Thanks in advance for your inputs.
It�s only an issue until it happens to you, and yes this particular problem is an issue on these and many other plated cylinder aluminum block engines.
Not to derail but what would you say is the Fuel Air Ratio at which point you need to check the injectors. Ideally you want to see 1.00. What about 1.07, 1.10, 1.2?
The biggest problem is that DME acually works as if it were two separate three cylinder engines, bank 1 and bank 2, each bank gets the same injector pulse time, and is checked by first/front 02 Sensor for that bank. If one injector on a bank becomes clogged/restricted, the other two injectors for that bank will richen to meet the OVERALL air/fuel ratio target. And vise-versa if one injector leaks/overfuels, the other two will overlean to meet the OVERALL air/fuel ratio target.
As far as air/fuel ratios go, Lamda 1 is "stoichiometric" or "stoich" which is the best ratio for emissions/catalytic converter efficiency (14.7/1), but is neither the best for power or for economy. The best fuel economy is reached when there is enough air to burn all the fuel that is delivered to the cylinder ( 17-19 AFR*), the best power is reached when there is enough fuel to burn all the air that is delivered to the cylinder ( 11-13 AFR*) ****(depending on engine/head design and fuel used).
This is sort of an overview, it can get a lot more technical/detailed than this..
I just bought a 996 4S with bad bore score and piston slap as a project....
Rebuilding to a Nickies 4.0, having the heads refreshed with minor porting and installing new injectors.....among a list of other stuff a mile long.
Outside of dyno tuning I will be at $13k USD for parts/services.....with my rebuild labor rate of $0/hr
Definitely not just a Porsche issue.
Near the end of 2020 while doing a PPI, I diagnosed bore scoring on a 2017 Toyota.
I could see deep scoring through the spark plug hole.
It was just out of warranty, but I sent the original owner back to discuss it with the Toyota dealer.
The scoring started LONG before the warranty expired.
I haven't heard an update.
Wow I thought mine was bad and Jake Raby said it was "stage 3." Here are some pictures.
But compared to these mine seems pretty minor. Nickies are not in my budget right now so I found another set of cases with no scoring and will be "refreshing" the engine over the next couple of months. I expect to be all in for less than $5,000 plus my labor. If i can get another 5-10 years and 50,000 miles I will be happy.
11+ years ago when I had my intermix from a cracked head and Jake, my indy and the dealer said I had no choice but to get a new/rebuilt engine I spent about $1,500 in parts and fixing the head and then my labor I I got another 11 years and over 50,000 miles before my recent problems so I am rolling the dice.
I have a 1999 and to me this is ridiculous for a $100 k car. To need suffer with bore scoring, crack cylinders, ims and crank seals, ims bearings, aos, cracked coil packs, cracked coolant reservoirs, rattling mufflers, seat belt sensors, rattling hard top, leaking spark plug tubes, crappy thermostats temps, water pumps to replaced at 60k miles, what else? These cars are a bad value. Fun to drive ... but really to pay out off pocket to fix a badly engineered design car is stupid. I’ve enjoyed mine but really these cars are a roll of the dice. A ppi doesn’t guaranty or mean that bore scoring won’t start 6 months after you purchase your car.
Yeah my piston didn't look near as bad as e30's looks, but it was "clacking" pretty badly! Jake has a good recording of my car on his youtube channel Rennvision. Titled: Bill's 996 C4S Arrives..."
Edmonds total cost over 5 years for a 2020 Carrera is $96k for years 1-5, based on a purchase of $120k. So at least the items you mentioned above are about 1/2 the total cost of ownership.
All cars will eventually breakdown with something that is unique to the model. 993, 964, etc. It's inevitable. No car will run forever without problems. None. Zero. Zilch.
I'll happily keep my 02 and have the engine rebuilt when it goes. And it will eventually go. In the meantime, I'll do everything in my control to prolong and prevent. I've driven all the new Porsche's at Barber Motorsports on the track and while I am impressed with the speed, automation and technological nanny stuff, they are not as much fun as our 996s. There is no analog, mechanical feel. They are big, heavy and neutral. Fast, very fast, but not as much fun to drive.
Enjoy the 996 for what it is. A great car that will eventually need an engine rebuilt. Just like every 993, 964 and Toyota Camry if you choose to keep it long enough.
I agree but I think there is a difference between a car dying at 100k, 200k+ miles or having your engine disintegrate at 40k. Plenty of cars have their weak spots, especially sports cars but the M96 seems especially prone to catastrophic damage that can happen at 5k miles or 250k miles.
Motoo,
Can't argue with your point especially for 80-100k a new car 20 years ago. However, Porsche tells us that over 70% of all Porsches ever produced are still on the road or garage, and that number arguably may be closer to 80% of all 911s. This is not the case for BMW, Mercedes, Honda, Toyota, etc.
As such, the older the car the more the problems, and when you subscribe to Rennlist, you get the problems fed to you in a concentrated manner thru a firehose.
The point I am making is that not all 996/986/997/987 have the engine problems. My 02 996 is 19 years old. 55k miles. I have tracked it over an estimated 80x. Stayed on top of every potential issue and have had a blast with it. Maybee I am lucky, or maybee the odds are that a smaller portion of these engines go catastrophic than we may believe. I wish I had concrete stats to give you by timeline how many go bad and when. But I don't.
What I do know is that once my engine goes catastrophic, and I hope it's not for a few more years, but once it does, I will give Jake a call and get it rebuilt so I can have the car for another 19 years to enjoy.
Yep, I bet Porsche is wishing they did things a little differently with every car they ever produced. But all in all, in my humble opinion, I would buy my 996 all over again.
After following this forum for 2 years, reading and watching everything about 996s, and then listening to 2.5 hours of great, detailed, discussion from experts in the field in Part 1, I now find myself asking why some M96/97 engines DON'T get bore scoring more than asking why some DO! I personally think the majority, if not all, will eventually suffer the fate if they don't to some degree already. Possibly many have asymptomatic scoring? some may only present with some excess oil consumption? acceptable "lifter tick" sound? who knows. Can you really escape it with proper gasoline, proper warm up routine, fresh injectors, accelerated oil changes, etc. I am in the lucky group so far, having put almost 30k miles on a now 50k mile 03 4s. No signs of it, barely burn any oil, healthy UOA......but why?
With all due respect, here is the best advice I can give anyone who owns a 996 and can't stop belly aching. Now may be the time to sell it. Prices have gone up. Take your money and buy a Honda. You will be happier.
If you own a 996 and are looking to share ideas with like minded folks to improve your 996, keep posting on the forum. It's awesome. Thanks for the value you add.
If you don't own one and are lonely and just looking to talk to someone, go join the Honda forum.
I don't know enough about these to wonder whether at the time the motor was a radical departure in technology or materials (aside from being liquid cooled), or whether the companies financial situation when these were conceived forced them to cut corners. I get the impression that a lot of these cars, not just Porsche, suffer from some issues, have expensive maintenance, etc. I knew that coming into this. I can safely say my 2016 Town and Country van is probably better made in a lot of ways. So is my work van. Different vehicles with different purposes. That said, I'm looking forward to a new year of investigating its condition more deeply after doing a lot of reading. Wherever it leads it leads. New injectors and one of those UOAS systems are the two likely candidates, though dropping the pan and looking at the bores as well as doing some more investigation about IMS and RMS condition are on the list too. Being a tip, I'm trying to come up with a logical order to do this so I'm not dropping the motor and or transmission twice.
Correct. Anyone who has rebuilt a Porsche with nikasil bores knows that if the engine is running rich that the bores will wash down, glaze the bores over, and take out the piston rings. This is why we mandate new injectors are fitted on rebuilt engines, along with a new MAF and primary o2 sensors at bare minimum. Those who know smoke test their intakes and check for vacuum leaks that can negatively affect fuel trim and increase wear. Seen too many instances where parts get reused when they are the reason why the engine failed the first time. Not enough money to do it right the first time but plenty of money to do it twice.
I'll just add that Porsche is the only automaker to ever use Kolbenschmidt's Lokasil process and only on the M96/M97 engine from 97-08 in Boxster, Cayman, and 911 models. No manufacturer has used this process since.
The more I read on bore score, the more confused I get.
It appears that every M96 that has been scoped has some degree of bore score ?
True or False?
Does anyone have images of cylinders with 60k or 70k miles on them with no bore score?
This gradient of bore score, is any bore score acceptable or do cylinders have to look fresh for a M96 to be free of immient bore score?
Are all M96s going to fail from bore score?
Other 996 forums world wide, of which there are many with thousands of members, (obviously with some redundancy) don't seem to have as high a percentage problematic M96 engines as on Rennlist.
How does a M96 last 150k miles plus with no problems other than regular maintenance?
David, join the free webinar LIVE on YouTube next Thursday and ask these questions. These are really good thoughts. I've become friends with Hartech's main rebuilder (Lee Jenkins) on Facebook and he reports daily. He rebuilds many M96/M97 engines every week and says that cylinder bore scoring is the main problem they see with these engines. We're planning on doing a Rennvision webinar with Barry Hart and Lee Jenkins soon. Barry brings a wealth of proven experience with Porsche engines to the table. Stay tuned! I would like to invite you to become a Rennvision member!
This interesting for me as my 1999 m96 has just been delivered to FSI for a rebuild and there is no mention of new injectors being included in the proposal. I'll ping FSI.
As these cars age its likely that the ownership will change hands and the buyers will start becoming a more enthusiast based breed. During the early years of ownership the dealers take care of the issues and the owners just drive the cars and trade them in when done. When the cars start becoming vintage you will start seeing people who want to preserve the car and bring them back to their original state. Its not just a Porsche thing. During this process problems will be found an that's when Forums provide a wealth of knowledge but they also typically attract people with problems that need answers. I would be willing to bet that majority of 996-997 owners who don't read the forums have a very low stress ownership experience.
That is a very good point that I was thinking about. I don't care for an increase in power/displacement and would potentially consider an RND engine as a rebuild option. Looking at the list of what the build includes I also didn't see any mention of new injectors. If auxiliary parts like AOS, spin-on filter adapter and filter, oil filler tube are included then why not injectors, if they are such an important piece to the puzzle. Hope Charles can chime in.
Thank you for saying this! Is it an unavoidable fate or does following the recommended steps can really help prevent bore scoring. I'd also like to better understand the difference between minor scuffing on cylinder walls as compared to scoring. What's acceptable and what's not. We often see the advanced scoring examples but there have been several examples posted here and in 997 sections showing minor scuffing. Yes - will be joining the webinar!
If you build it like a 2 stroke plated dirt bike cylinder, it�s probably not going to last as long as it could. As for the sealed bearing inside the engine, the same applies. All or nothing with rebuilds on these engines, and the costliest seems to be cylinder reworking. Lots of nonsense from these two items. Don�t forget lots of other Porsche engines suffer from this cylinder damage.
I remember in my dirt bike days, the concern with cold seizure, running a 2 stroke hard before thoroughly warming it up, and it was definitely a problem. When those cylinders and pistons went south it was bad as well, and not replacing bearings and seals was regularly done but not the greatest idea.
The 996 has a great chassis , great suspension and brakes, but the Achilles heel is the engine and cooling system problems IMO.
On a recent build I did pay for all injectors to be cleaned and tested before placing back in car. Engine builder said no reason to replace if test was good after cleaning.
With out removing can you test injectors?
Sorry if a silly question
Originally when the RND program was developed for SSF, it was planned that an install kit would have to be purchased for there to be a warranty, but that never happened. What was supplied with each engine was determined by SSF. There are plenty of other items that also need to be replaced that are not included like flywheel, clutch, flywheel bolts that isn't traditionally part of a longblock. The reason why the AOS was eventually added to what was included was because shops were using non-genuine ones that were failiing; same with the oil filler tube and even the oil cooler itself after SSF had shops again reuse these items and cause damage to the rebuilt engine.
However, injectors have always been recommended as part of the RND installation directive but the reason we don't include them is that shops want to source them and sell them to the customer directly, so we let shops handle purchasing these parts and other components required for installation.
Since all RND Engines come standard with an IMS Solution, they would have the spin on oil filter adapter and spin on filter.
We've seen several instances where an injector is sent out for cleaning and testing pass and then fail several thousand miles later. Injectors cannot be rebuilt, only cleaned. Internal wear that can cause injectors to leak, for example, can't be fixed. A well known Porsche shop owner and PCA Tech Committee member had a factory replacement shortblock score after a few thousand miles. He had the injectors cleaned and tested. It ended up scoring the same cylinder that had previously failed. Injector was to blame. This is just one case but we've seen this time and time again.
Thanks for answering, Charles. That definitely makes sense. I'd say that flywheel, clutch and bolts don't really play a role in whether bore scoring happens or not, however, injectors do. Per Pelican Parts they are either $33.75/injector for Bosh OEM or $306.37/injector for Porsche ones. Not sure what's the deal there price wise as Bosh is the OEM supplier and the part numbers seem to be exactly the same between the two.
How do you know that you've been doing too much research on this stuff? YouTube suggests videos like this:
You Tube
Similar topic and sounds like even Toyotas have their share of problems!
you better believe I have new injectors going in my 4.0 Nickies build. I've got a shipment of 91 m96 rebuild items coming tomorrow. On top of the 14 I've already received!
Easy. Turn the engine on, drive on the highway, and only turn it off to do oil changes.
It�s startups (and cold ones at that) that are the largest contributing factors.
Here are some technical videos we just released earlier this week on fuel trim, vacuum leaks, and injectors, among other topics presented by Tony Callas (Callas-Rennsport):
https://youtube.com/playlist?list=PL...u8OfQkDW2RmFSH
One has to be very wary of imitation fuel injectors these days. There are more knockoff garbage ones than good ones and it is very difficult to tell the difference, boxes are the same and markings are almost exact. $33 sounds about right, and $300 is thievery. Definitely buy from a reputable dealer for the best luck.
Yes. Bosch is making these injectors in China now so there are knock-offs everywhere. You need to purchase them from a reputable source. There are holograms on the box and serial numbers on them you can use to verify if they are genuine or not.
The problem we have right now is that there are no injectors anywhere to be had. We've had them on order for a while now and are expecting them in mid Feb. Sadly right now all that is available are the injectors from Porsche which are the same, but just in a Porsche box. That's why they are $300 ea.
My source for pricing and most parts is Pelican Parts so hope they are considered reputable enough. I'm definitely in agreement about shady distributors. With so many companies moving production to China I'm curious where the shortcomings would be? If Bosh has a factory in Germany and in China is it fair to assume that injectors produced in their factory in China are junk as compared to those in Germany?
I just received a response from FSI and they said this was an oversight and that the existing injectors will be replaced with new. This what I would expect from FSI. These guys rock!
With the refreshing of my motor I am planning on putting in new fuel injectors. I found a set on eBay that are quite reasonably priced with this note. I am asking if any one has any knowledge on this.
Porsche 911, Boxster Upgrade Fuel Injector Set
Bosch # 0280150455 has been Discontinued by Bosch/Porsche
Direct Fit Bosch EV6 - 4 Hole Spray - Plug & Play Upgrade Fuel Injector Set
Includes 6 Bosch Fuel Injectors and 6 EV6 to EV1 Adapters
240 cc/min @ 3 Bar - 43.5psi
23 lb/hr @ 3 Bar - 43.5psi
172 g/min @ 3 bar - 43.5psi
Product is Brand New - Bosch Original Equipment
Price is for a Set of 6 Bosch Fuel Injectors and Adapters
Product is shipped bulk, No Manufacturer Box
Free Shipping.
Bosch Ref #
0 280 150 455
Porsche Ref #
996 606 120 00
Standard Ref #
FJ849
The dealer also has a note with a new part number. Also RockAuto has a listing for Ultra Power FJ849 injectors that are only $35.79 each, note this part number is the same of one of the numbers listed on the note on eBay but it says theone they are selling are Bosch.
Bosch sends the injector to China with design outlines, China makes said injector for Bosch at much lower prices because it is communist China where people work for much less. Bosch has to quality control thesecinjectors because China won�t and it is worth it for Bosch because it�s so cheap to produce, again because it�s China.
When the Chinese factory realizes that they can make more money by cutting Bosch out of the equation, because they have the formula for production, they produce these with no or little quality control. After all when it fails who are you going to call to get a refund? And who would you possibly sue? When a company decides to do business with China, which they do often to try and compete monetarily, they get this .
I know a few companies that deal with China for manufacturing, if you have one factory build the complete part, they are going to take that design and sell it on their own for much less, because they don�t have to design it. Most companies I know have multiple factories building individual parts and that keeps the counterfeiting and thievery at bay for the time. China doesn�t play by the same rules,
Sorry I did not see the recent post from today abut injectors. I am guessing the ones on eBay may be knock offs as it was only $150 for a set of six. But the new part number from Porsche, 996.606.121.01 are only $105.82@ and my friend at the local dealer gives me a good discount on parts, about the same as some of the dealers that discount on line and there is no shipping so I will probably go OEM. I am wondering if the new ones from Porsche are two hole of 4 hole though?
The only knowledge I have is that the majority of parts sold on eBay are cheap Chinese knock-offs.
I wouldn�t risk an engine rebuild to save a couple dollars
Because the base part number has changed,(not just the revision end numbers) from 120 to 121 that indicates a significant change, I would suspect it to be the EV-6 plastic body style (4 hole) with the ' Minitimer EV-1 style connector"..
I don�t really think about this at all. Come spring, I will get in my car and drive and not think twice about this. 😀😀😀 Worrying about a 996 is so 2020.
I couldn�t agree more, for both of my 996s, they are a blast to drive. I do the best I can with oil and maintenance. Plan on driving them until they go kaboom!
I whole-heartedly agree !! Last time I checked in 2019 I was at 14.7cents Smiles Per Miles $$$$,,Try to beat that one for worry free driving !!!
https://rennlist.com/forums/996-foru...-per-mile.html
I have no firsthand experience but Jake and others commented that the injectors can�t be opened and therefore the internals can�t really be cleaned. That seemed to be the driving rationale behind the replace vs repair recommendation.
Orings and screens in the top of the injector. They can be ultrasonically cleaned and flowed, but after spending all that money on a new engine, and knowing it doesn�t like injectors that wash cylinders down, are you going to trust 18 year or older injectors?
When I was researching hot rod engines from the 60�s and 70�s, cylinder bore wear was always a concern and under discussion for rebuilds and longevity. Nothing new.
[QUOTE=Mike Murphy;17209387]When I was researching hot rod engines from the 60�s and 70�s, cylinder bore wear was always a concern and under discussion for rebuilds and longevity. Nothing new.[/QUOTE
Most of those engines could be remedied with a machine bore to the next service size, no plating or sleeving needed. Lots of minor scuffing could be cleaned with a hone, not so much with this engine.
[QUOTE=cdk4219;17209510]
Sure, but it was still a rebuild at 60,000, 80,000, 100,000 miles, not unlike these engines. It just costs a lot more, but then so does everything else for this car. Which makes one wonder if a $20k rebuild is really that crazy for a car that costs $100k new and has a $90 TCO add-on for a total price of $190k over 5 years (Edmond�s TCO estimates).
[QUOTE=Mike Murphy;17210010]
Maybe valve job at 60 to 80, the thing that took old engines out was either leakage from seals essentially made from rope, or overheating issues clogged radiators or leaky water pumps. Depends on what you would like to 25 thousand plus on. If it makes you happy, then give Jake a call.
Good webinar last night. Mostly reinforced what has been already said many times and appreciated having Tony Callas there and his take. One take away that I walked away with was something that he said at one point.... In the many PPI's they have done, just about every car had some sort of wear on the cylinder bores. The big and important part is recognizing what is acceptable and what is not. To me, it sounded like these cars will develop some scuffing on the bores which is normal and not something to go crazy about. I'd love to see more focus and examples of this of what is acceptable and can be considered as scuffing vs scoring. Most of what we see are extreme cases. Jake did confirm that looking at this via bore scope will exacerbate the issue often due to the bright light and magnification. He also did say that some scuffing is a byproduct of the dowel pin that helps secure one of the rings and that is normal.
Second big take away, courtesy of Charles was.....drive the damn car! Follow the correct procedures for warm up but do drive it!
I know it's a stretch but....
I made it till the car owner came on it was past my bedtime, sorry bud, I�m getting old... that said it was informative and enjoyed the info. I see myself looking at the exhaust tips and listening closer to engine noise. I don�t have much time on the oil or miles for that matter, but I think on a day that�s a little warmer get about there warm it up and drain it out, send a sample, drop the pan and look in there with the scope. I have the magnetic plug to put in. See what�s in the pan, look at the bores and decide which Driven oil to use based upon findings. I have a bunch of manometers so I�ll see if I saved the original oil cap and test that too.
I missed that part as well - bummer. That's a sound plan, nrp3. I need to test my AOS to see if it's causing oil consumption and if I end up installing the UAOS I may do injectors as well as I'll need to lower the engine already. My oil change is in about 3k miles so I'll be dropping the sump, poking around with scope and doing UOA.
Yes, a lot of what we covered has already been covered. The main goals that I had for these webinars was to put all the information as part of one resource material, and to have people on the panel that represent every facet of what's involved. This is why Lake, and Tony were asked to be there, as well as Wildbill. There's so much back and forth on this, that people need to hear it all at once, so they can weed out the BS, and streamline their decision to keep the car after a failure, or sell it as a roller.
A lot of bore scoring is misdiagnosed. Some cars that have it, are diagnosed as "bad lifters" and those engines do have scoring. On the flip side, a lot of engines that see scope inspections are misdiagnosed because the person doing the test can't differentiate normal cylinder appearances specific to these engines, from actual bore scoring.
Remember, every mechanical thing ever created has two facts related to it. This varies from roller coasters, to aerospace, to Porsche cars. The fact is that the only guarantee is if the doesn't fail first, it will wear out. Every engine starts to die the day it is started for the first time. Don't ever forget that.
You can take the bore scoring failure, turn the whole thing around, and create something that the factory never could. IF you LOVE the car, bore scoring can be the best thing that ever happened to you, as long as you can afford to do it right.
This failure is much different than the IMS issues. I also know that the IMS issues did NOT hurt the value of these cars; most buyers had no idea that the IMS issue existed until AFTER they bought the car. What hurt the values of these cars was the economy at the time. Look at Mercedes, BMWs and other cars of the same era- same deal.
Why are the cars bringing more money now? Well, its because people have figured out that these cars are the last of the analog Porsche cars, and that everything that came after them got too big, too complex, and too de- sensitized. These cars are also better and simpler than the newer cars, and this will continue to be recognized moving forward.
TOO OLD? Hell man I'm 70!
Seriously though I see you are on the East Coast so it was late and my part was boring(pun intended) compared to the rest of the presentation. My part was to share the issues I went through on my journey to and through bore scoring. I went from no knowledge, to knowledge, to the issue, to denial, to finding the fix, to having the fix performed and being insanely happy about the outcome.
There is a fix and, to me, a very satisfying fix.
Not that I wasn't interested in what you have to say. I fizzle out early these days. I'm going to dig into it and see what the real condition of this thing is and try to post some hopefully useful pictures along the way.
So I got inspired to get off my @ss and start on this. So here are the tips and I can get better pics of them if needed now that I�ve removed them. I have a used set of Fister mufflers to put on, so nows a good time to (and easier) to scope the spark plug side of the bores. That is once I figure out how to get those nuts off of the muffler bracket. Found the license plate light connector is wrecked and a bunch of hardware holding the bumper cover were missing too. Oh well.
Google reported back that we had 176 people watching the LIVE feed. The live counter is never accurate. It said 42 viewers. Anyway, it was a great webinar with a wealth of information that applies to the M9X engines.
For those that missed the LIVE feed, you can view both parts of the webinar as a member of Rennvision.
You Tube
You Tube
I really enjoyed the webinar(or at least the first 95 minutes) last night.
I got up early and watched the rest this morning before work.
A lot of the info I already knew.
The SUMEbore research info was amazing!!
I'm definitely going to watch the PCA Tech Tactics Live next week to learn more.
I also watched Tony's Fuel Trim and Vacuum Leaks videos that were referenced last night.
Both were very well done and every Porsche owner that DIYs should watch them too!
Fuel Trim:
https://www.youtube.com/watch?v=HW7B...ature=youtu.be
Vacuum:
https://www.youtube.com/watch?v=wVLu...ature=youtu.be
I know a lot about fuel trim, and using it to troubleshoot domestic & Asian vehicle issues, but I learned a LOT about Porsche fuel trims!
It�s sad that the M96/97 can�t catch a break. Just as they are becoming sought after classics. Bore scoring seems to be a matter of when, not if. You don�t want to be the last owner, unless you picked it up for a steal.
I�d hate to see this tank the market and dampen the enthusiasm for these cars.
Makes me wonder if we�re all just drinking the Porsche kool-aid and their engineering does not live up to the hype.
@Flat6 Innovations
i submitted a ticket to discuss a project car I bought knowing it had some motor issues. I think your diagnosis based on the described symptoms alone was spot on.
Those look normal to me. They will never be perfectly clean but the sooty ones that typically indicate bore scoring are much more deep black and have an oil residue to them. In some cases I've seen black droplets actually fly out of the exhaust. Look forward to seeing bore scope photos. Next oil change I'll be doing it from both ends.
I got the brackets off without breaking anything. Tomorrow I�ll pull the plugs and scope that side and try to take useful pictures. Once the exhaust hardware shows up and I get the Fisters on, I�ll run it up on a decent day and pull the pan to see what�s in there as well as scope the other side.
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These look great from the top. Some very minor scuffing but not something I'd personally classify as scoring. Plugs look clean too. How many miles on them?
Maybe 500 miles since I bought the car in august. I know jake has mentioned you may see something related to a ring being pinned? I will do this from the sump soon. In the meantime I�m out starting the same procedure on the drivers side bank. I�m not super worried either, but I respect the consequences of not doing further maintenance.
Yes, the pin comment precisely. Again this looks perfectly normal, to me at least.
Doing some more reading and thinking I've come to a topic of fuel washing off any lubricity left by the oil, as fuel is a strong cleaner plus added ethanol increases this more. I was curious about what positive/negative/neutral effect would adding something like SeaFoam would have while filling up. It is described as a cleaner but also something that adds lubricity to the fueling system and the fuel itself and in turn helping lubricate the upper portion of the cylinders. In theory this would make sense as it would help to decrease the cleaning effect of the gas and the lubricity could potentially limit the risk of scoring. I am aware that scoring starts at the bottom of the cylinder bore but like it was said many times, it's never a single thing but a series of events.
I did see the mention of Sea Foam during the discussion and almost bought a can. I used the techroline in my work van as I sit and idle a lot so I have some place warm to go during work and could see a smoother idle after that. May be butt dyne psychology too. I have a bottle in the tank of the Porsche right now and a couple more bottle on the shelf. I might switch to sea foam to see what happens. New injectors are likely one of the next projects and a switch to Driven.
Once I get the parts to put the exhaust back together, I'll take it out for a run when the weather is decent, drain it and pull the pan. I'll take pics from the sump then.
Now unfortunately, my skills at using the scope from the bottom end weren�t so good. Maybe with a lift it would have been easier to maneuver.
So, roughly 1500 miles, seven months, Liquimoly drained out, new filter, DT40 in and six new injectors. Now off to run it up to temp and get some cam deviation readings.
I get the impression it meets whatever the current spec is. I went with that oil for my first oil change last year not really knowing much about the choices we have for oils. This year I went with DT40 and will send another sample at the end of the year once I get some miles on it. The viscosity warning, I�ll have to do some more reading on and hopefully those with more experience will voice their opinion. The report other than that sounds good in my limited experience.
The trends over time are what's important. Even your first UOA with the current DT-40 will not be of too much meaning since it will still have some of the recent LiquiMoly in it. Enjoy putting on the miles!
If I remember right, you also replaced the injectors so it's nice to see fuel dilution being in the green. I'm sure the oil was ran with the original injectors for majority of its life so it's safe to say that they were not in bad shape. With that, I'm curious to see if that number will drop after the next sample is sent in. Now go drive your car!
I just ordered new injectors, Skip's UAOS, and a 997 GT3 shifter. Next oil change will be a little more expensive but that's the price you pay to be an addict! Curious how future UOA will react to the new injectors, but time will tell.
I'm in similar boat! Have a fresh set of injectors sitting here along with the UAOS kit from Skip. Goal is to tackle both at once. Then I'll do an oil change and my first UOA to get a base line. I purchased my car in October with 77k miles and just ticked over 83k yesterday. This included the maiden voyage from FL totaling about 1500 miles so it's definitely getting driven. I immediately did an oil change when I got home with DT40 and then a second one at 80k while the IMS was done. I upgraded to a spin on filter at that time as well.
I did change the injectors before the sample was sent. I�m still not sure about the viscosity thing, though maybe the mixture of the Liquimoly and residual oil which I have no idea what it was. So, yes I�ve been driving it whenever I have the chance. At the end of the season or next season depending upon use, another sample will be sent. AOS, RMS, and IMSB, next up.
The first service after changing oils is a waste. Cross pollination is such a huge issue that I don't even do a UOA on the first service after a swap. I run 1K miles on the new oil, then dump it, and perform my new UOPA after that oil service has 5000 miles on it. Doing anything else just wastes money, and doesn't show you anything.
People want to see instant results. That doesn't happen accurately.
