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YOUR RESEARCHScored bores are scaring me off
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injectors have different failure modes, electrical/mechanical/clogging
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One issue is injectors have different failure modes, electrical/mechanical/clogging
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Reported cause
The one cause of bore scoring that gets more attention is starting the engine in extreme cold.Problem is said to be one of insufficient cold temperature clearances.
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Standard injector life is around 80K average last I checked, They get progressively less
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For the mechanical injection on the sprint cars, they are simple and get cleaned between
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Then to start my ownership it got a full service with clutch/IMS/RMS/AOS, fresh tires and replaced airco condensors & cleaning of radiators.
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Suggestion
I've used the guy up in I believe issaqua Washington,,, most big cities have a injector service company, its mandatory for most diesels and commercial rigs o keep their clean idle status.
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Reported cause
The one cause of bore scoring that gets more attention is starting the engine in extreme cold.Problem is said to be one of insufficient cold temperature clearances.
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Suspected cause
I have always started my engines and drove away slowly getting everything coated with oil and a little bit of temperature in the oil, then taken the engine in second gear to a full throttle high RPM pull takes about 3 seconds,( if it is an engine I didn't build myself that I suspect may be a bit too tight), then I let it warm up the rest of the way slowly before any prolonged full throttle high RPM pulls.
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Hey folks, I won't make another "I'm thinking of buying a 996" thread like so many.
But I am, however I'm not put off by IMS/RMS issues, I planned on dropping the tranny and doing IMS/RMS and clutch kit after buying a car. No big deal.
What I'm more concerned about is the scored bore problem, I know once it gets further along it creates noise, esp during a cold start, blue smoke at start up, usually on one exhaust pipe (with the bad cylinder).
I also know it can happen due to oil starvation on high cornering speeds, and very cold starts when the cylinder and piston expand at different rates.
Should I be worried or is it rare in warm climate cars? It doesn't seem that even PPI always catches the early signs of a scored bore.
I've been looking at cars with higher miles (100k+) and I've already seen a few, I'm assuming that if the motor was going to score its bore or blow a D-chunk it would have done it already.
Incidentally I'm experienced with cars and have a very good ear for odd engine sounds, I have a good track record with knowing something sounds off.
Thanks!
Your 996 is a 1000 times more likely to experience a mechanical failure due to mice...
Keep traps in your garage and never, ever, keep your garbage in there, no matter what time of year.
The bore scoring noise confuses me. There is a video from Flat 6 (Jud Fink) giving an example. What I don't understand is how does a scored bore make a sound like worn lifters ? I can't understand visually what makes the clatter.
You Tube
There are lots more if you google "Bore scoring Youtube"
The one cause of bore scoring that gets more attention is starting the engine in extreme cold.Problem is said to be one of insufficient cold temperature clearances.
Just buy your 996 from a warm climate?
I think mice have taken up residence in Gonzo's head.
Having recently pirchased my first 996, I also was concerned about bore scoring. From my research indicates blue smoke on start up, increase in oil consumption and maaaaybe some noise are early symptoms. You can bore scope the cylinders through the spark plug hole and/or the bottom end of the engine to look for damage. Dropping the pan and pulling the oil filter to inspect for debris can also lend clues. This all can be part of a PPI on a car you are serious about.
That said, I did none of that and bought a car with a pretty clear past (service records, two owners and 55k miles) and my gut. I trusted the seller and my ear. No weird noises, no signs of oil consumption etc. car ran great. Three months later and 6k miles and still runs great. I changed the oil, dropped the pan and tore open the filter. All were clean to my great joy.
Do do your due diligence. Seems like you have been around enough to determine what that is. Then drop the hammer and never look back.
The piston motion will either rock axially about the wrist pin axis where the skirt strikes the cyl, or the piston will slap radially about the big-end axis where the piston skirt strikes the cyl wall.
Don't forget the cyl is a nice echo chamber, or audible reflector.
Yes, move to the warm climate and own a 996.
If you can live with the worst case scenario (however much it might suck) then quit worrying and go for it. Do your due diligence and just accept there's a chance things can go wrong. I'd equate your current logic to not wanting to buy a nice car because someone might pull out in front of you and wreck it. Yeah, it can happen, it does happen - but you're missing out on the joys of ownership. What's the old adage? Better to love and have lost than to never have loved at all?
You have described Piston Slap. Bore scoring is a different noise ? If the scoring is so bad it has ovalised the bore ,then yes, that will sound just like Piston Slap.
Or the score marks are so deep you loose the oil film.
IT seems more likely on Bank 2 because the wrist pins are not offset.
Ok. I listened to it twice, although my laptop speakers aren't great, that sounds like a piston moving in the bore. In an air-cooled engine the sound is more of a ringing noise. I can only surmise that the water jacket provides a bit of damping effect, but it sounds like piston striking the cyl wall to me. Meh - I could be wrong.
This thread is a perfect example of what causes a "Rennlist" complex. If you read these boards consistently, you will convince yourself that your car is seconds away from a nuclear meltdown at all times. Like the block is made of paper mache and the pistons from gummy bears.
The reality is that Porsche has been at this a while and sold a ton of 996s through the years. Are there known issues? Yes - but owners have found ways to deal with them.
Do all bores have scores in them? Yes. Do some score worse than others? Yes. Just watch the oil consumption, which will not be 0.
Pick and good one and maintain it. These are tough little cars! Don't be afraid either.
Bore scoring is easy enough to check for in a good Indy shop , it will add a little extra to the cost of a ppi but worth it . They just have to pull the spark plugs and scope the bores
Thanks everyone, seems if I make sure I get a west coast car which hasn't been used in very cold weather, the car hasn't been tracked etc then should be good.
I've had a 3.2 carrera and boxster before so I know these engines do use some oil.
As an extra check if/when I buy a car, when I'm doing the IMS/clutch I will pull off the oil plate from the engine and scope the bores from there, I have a camera myself so it won't take me long to check.
You might consider an early 996 if you can stand the headlights and absence of glovebox! I understood the 3.4's have less issues for bore scoring if that is your concern.
Volkert
I've said this before and will say it again ... there are plenty of cold climate cars out there that have never been driven in the winter. Like so many other things with these cars, it's all about the service history and knowing where and how the car was driven.
To be specific, AFAIK, it isn't the driving in winter, it is the
starting
in extreme cold.Meaning no block heater,no heated garage,left outside for 24 hours in very cold temps. We had this misunderstanding a few weeks ago.Not mening to split hairs but there seems to be no problem driving in extreme cold, just starting without some 'help'. Just want to avoid a panic of "Oh , I can't drive it in winter??"
Uh huh. Never...and I mean never...underestimate the ability of mice to damage your 996. I don't want to unduly scare anyone, but it's not limited to the motor. They can affect the convertible top mechanism, the brake pedal and the coolant system. Have you ever seen a water pump impeller after it's been chewed on? Devastating...
....some believe the scoring appears to be the result of the block heating and cooling at different rates from one end to the other. The end cylinders end up getting out of round. The theory is that if the car was cold started, then driven hard before all the temps equalized and got up proper levels, and then after being run hard, it gets shocked cooled by shutting off without a cool down period, the block expands and contracts at different rates along its length and bam, out of round bores.
That's one theory, anyway.
EVERY car out there has some kind of catastrophic failure mode. BMW, Mercedes, Ford, Chevy, pick your poison.
Choose wisely, take care of the car, let her warm up and cool down properly, run Driven oil and change it every 3,000 miles, and enjoy life.
Thata interesting. I had a 3.2 and a Boxster also. These 996s aren't that much different from any ol' Porsche.
Like others posted, standard high quality oil can protect your at cold startup temps. My car came with 0-40 and is good down below the coldest temps I have started my car at (5F) and as long as you are gentle until warmed up, I don't think the scoring is that common.
Good point regarding the distinction between damage caused by cold weather starting, as opposed to cold weather driving. The point I should have made was that some percentage of cars in colder climates (like mine) go on battery tenders and hibernate, unstarted, over the winter.
That said, I am guilty of linguistic imprecision. Mice may have gotten to my cerebral cortex.
This is nuts. I DD a 996 that was mostly parked outside in the middle of Boston winters and suffered ZERO scored bores. Will the hysteria over this car please just stop. Good grief.
I posted this in another thread, but when it comes to mice it is worth noting-
a lot of people fault Porsche for the bore scoring and IMS issues but they fail to look at the big picture. The explaination for bore scoring is quite simple, actually. When you park your car in the garage on cool/cold evenings, the mice are looking for somewhere warm to sleep. They will crawl into the exhaust and nestle next to the catalytic converter. Sometime during the night they discover that the special platinum alloy is quite tasty and begin to chew away at it. This occurs night after night until one evening they've completely chewed through the cats. Once they find an open path they will discover that one of the exhaust valves are open. This is usually cylinder number six as the way the engine is balanced from the factory, number six exhaust valves are typically open when the engine comes to rest. The smaller more adventurous mice crawl into the cylinder and bed down. This typically isn't an issue for most owners as the mice wake up and head out to search for food before the car is started. The problem surfaces on the morning a Porsche owner starts the car before around six AM. The tiny mice are still in the combustion chamber. When the car starts and the piston reaches TDC, they are crushed. It's the little mouse bones that begin to score the bores. If you keep your garbage in the garage this can happen night after night, eventually leading to engine failure. Of special note; most people don't know this, but young mice are actually a bit claustrophobic. This is the reason you see the 3.6L cars exhibit these failures more often. That little bit of extra displacement is really attractive to the little guys. This explains why you can have a 3.4L car and it would be OK, yet your neighbor with the 3.6L can be affected. Most folks think there is no way to predict an impending score if issue, not true. When you first start the car, plant your foot to the floor and hold the engine at redline for 5-7 seconds. Have a friend look for tiny mouse droppings shooting out of the exhaust. This HAS to be done at cold start as once the engine is up to operating temps the mouse droppings will vaporize. If you find droppings, a cheap fix is a bit of D-con. $5 fix. Done.
So summary I guess, if you are scared about buying a high performance sports car, then don't do it! If you don't, do your homework, be prepared and ready to walk away if there is something which puts you off. My car is now 19 years old and I am the 6th owner. Who knows what happened to the car? Mine had a good maintenance history, relative low mileage but no garage queen (so driven regularily), well maintained (which a good mechanic will be able to tell you) with original parts and tires. Then to start my ownership it got a full service with clutch/IMS/RMS/AOS, fresh tires and replaced airco condensors & cleaning of radiators. I plan to do chain tensioners etc in next 2 years. **** could still happen but I think I am off to a good start! I think that is the way to approach it. Don't go out to find the best & cheapest buy. It can work but you'd better try to find a good one, enjoy it and be prepared you still might need to do an engine rebuild somewhere along the way.
Funny you mention that, my 2004 BMW R1150GSA has been making this god awful smell when I start it up recently, smells like hot rotten corpse.
I've looked over it lots of times and can't find anything. Last time I was warming it up I noticed some thick brown ooze on the bottom of the cat/exhaust, like it was seeping through a crack in the welding. Could be a mouse than crawled down the pipe and is getting cooked when I run it...
I think this weekend I'll poke my remote bore camera down there to scope it out and see..
Incidentally I just heard back from a job app I applied for, so texted an offer on a car I already went to see/drive. I'll see what the guy comes back with
Makes sense. There are some reagents you can get to determine what kind of biological remains are oozing out if you're worried that it might be something worse than mice. Like ferrets.
Those
little bastards are BRUTAL on cylinder walls.
No, unfortunately it doesn't seem to have an end in sight.
Many of the 996ers on here remind me of Chicken Little with some of the vendors playing the role of the sly fox who takes advantage of them...the other thing that sometimes comes to my mind is the old cliche; "a fool and his money..."
Exactly my point! There are certainly a few vendors capitalizing on fear. I refuse to fall in line with the thinking that Porsche grossly mis-engineered this product and that the aftermarket has it all figured out.
I love the aftermarket, however, the validation requirements do not even come remotely close to what the OEM demands. There is no comparison.
IMNSHO, Porsche did grossly mis-engineer the M96 engine. In fact, the courts have said so with the(lousy) partial make-good lawsuit. Further, engines which score bores so easily and have a grenade in the IMSB are two examples of poor engineering, or very poor mfg.
I've seen the run-out results on some of the IMS parts in another thread. They are - horrible. I have no idea if the engineering spec was so loose, or if the mfg was so sloppy but these are bad numbers. Shameful that the M96 engine was not taken out of the market, and better designed by 2001 at least.
There's a budding relationship between scored bores coming along and high fuel consumption. I'm speculating that maybe a injector/MAF/FI problem could lead to one or more cyl getting the oil washed out. Thinking that if one starts experiencing poor fuel econ that it's not being a lead-foot, but possibly the stoichiometric ratio may play a part in this.
It is what it is(or was what it was). I don't need a law degree to know that Porsche agreed to some kind of remediation for owners with prematurely failed engines.
BTW, I'm 4.5 for 5 in my civil court appearances(one no decision), and the prosecutors are 0 for 3 in criminal court, so - seems I'm not doing too bad.
If anything is going to really cause bore scoring its most likely leaky old tired injectors..
Rings like Oil on them not gasoline.
Standard injector life is around 80K average last I checked, They get progressively less
accurate after that, and that assume you didn't get a load of dodgy fuel at some point.
Good Luck
So basically what you're saying is Lokasil, piston pin offset, forged pistons, deteriorating skirt coating, piston slap, and cold climate impact are not contributing factors to cylinder bore scoring in these engines? It can all be contributed to faulty fuel injectors?
I believe a lot of way too much over-thinking goes in to certain problems.
And on a 20 year old car with relatively low miles, bad injectors are a higher percentage
cause of failure than potential mis-engineering considering how many cars make high miles,, its not all luck..
All of the factors listed can be contributors to the issue, but testing your injectors is a fairly economical
preventative maintenance item. Personally I've seen enough injector initiated piston fails that Its my
first check.. Before going all in on the rotating assembly..
I used to have access to a shop with a cleaning station, I went and grabbed a bunch at a
u-pullit yard to see what the spray patterns looked like.. More than half the sets I tested had
at least 1 bad injector in the bunch.. I went after 7 year old cars for the test units..
I�m always amazed how lay people think. A fuel injector will see millions of cycles in 7 years of driving and fuel isn�t the clean fluid it is thought to be. To think there is no wear in the injector resulting in leakage after shutoff with heat cycling and 50psi pressure differentials is insanely optimistic at best. I�m just a stupid $350/hr consulting engineer though.... I�ve never thought about problems like this.
The main reason people have ridiculous expectations surrounding these engines is the word �Porsche.� The expectations imposed on these cars by their ill-informed owners and prospective buyers IS THE SOURCE of paranoia. Sorry, I�ve met these evil vendors. They aren�t making exorbitant profits or spreading panic. They are actually working to solve problems to maximize the enjoyment of cars they love. The M96/7 and Porsche�s are not big profit sources for small businesses. They are labor�s of love. If you are looking for profiteering unethical businesses look to payday loan places and hedgefund managers, etc.
In that case, wouldn't it be easier to just say, "screw it!" and replace the injectors after a reasonable service life? How would a 996 owner test an injector that doesn't have an Durametric? Can they be removed like on normal cars?
You could say yes,, and be right.. Takes a couple hours to swap the injectors,, new ones every 80K ish,, not going to hurt a thing.
You might even notice a pickup in mileage with nice tight new injectors as well.
One issue is injectors have different failure modes, electrical/mechanical/clogging
The durametric + good troubleshooting skills will usually find a electrically failed one quickly.
Clogged injectors, will run you lean and you "should" get a check engine light if bad enough
durametric/pwis/scanner while running should show a lean condition..
A leaking injector (Mechanical fail+clogging) Is often less obvious, because the 3
cylinders share 1 O2 sensor, and its less of a problem at open throttle, the damage
occurs at mostly lower RPM (In my experience) when the injector drools raw fuel in to the engine,
washing down the cylinder walls. Worse yet on the Porsche engine,, the injector can drain after shutdown
straight in to the cylinder and then it soaks in fuel till the next startup or worse the fuel dries up leaving
varnish on the cylinder wall.
I see this a LOT at the track because a lot of race cars end up with used/old injectors because
for the most part racers are cheap bastards when buying certain kinds of parts,, its weird,
I've had a guy insist on a 2500 dollar titanium bolt kit, then bitch about the cost of rebuilding
his fuel pump (175 bucks)... Also installed a $35K engine,, and the owner would not buy
a new set of injectors for < 800 dollars.
As mentioned back a ways, I also send the injectors to get flow tested even if brand new,
DOA injectors are a thing.. Unfortunately..
Oh and if I've got the timeline right doesn't the water-cooled intro from Porsche coincide
with Bosche moving most all of their injector manufacturing to China?? (Coincidence? Hmmm.)
A misbehaving injector can also cause one exhaust tube to run significantly different
temperature, so a IR heat gun can give you a direction to look..
Cheers,, good discussion I hope!
pdx, where would one send an injector for flow testing? Your idea sounds very reasonable, if they are accessible and inexpensive enough. This is all new to me, so trying to learn what I can about these injectors. Thanks
I plan on buying new injectors for the 996 but I've used an injector service for my '80s BMWs. The owner is great to work with and his prices are reasonable.
I've used the guy up in I believe issaqua Washington,,, most big cities have a injector service company, its mandatory for most diesels and commercial rigs o keep their clean idle status.
I've also used 5-0 motorsports for my jeep ones a couple years ago.
I just googled around for injector cleaning services..
I thought Jake has mentioned at one point that many injector cleaning services aren�t always that great? That some injectors come back worse after cleaning, and for that reason, we should buy new?
Unfortunately quite a few misunderstandings about these issues which can be cleared up if you would like to read a long detailed report about it from our years of research.
It is available free from
[email removed]
.
Baz
These injectors can't be effective tested in a lab. The issues that we see are aggravated by engine temperature, especially when the engine is shut off, and fully heat soaked. When the engine shuts down, the engine will elevate in temperature for a few minutes before it starts to cool, all the while the injectors are being asked to hold at least 55 PSI of fuel pressure. With the engine shut off, the fuel within the rails and injectors also heats up, which makes it more difficult for the injectors to hold back.
Fuel leak down often occurs due to this, and the next time the engine is started, it does so with a puddle of fuel within the intake ports, or cylinders, if the intake valves were open on the cylinder at the crank position that engine shut down at.
In short, your lab tests mean nothing in regard to how the injectors function in the real world. We have seen injectors "test" perfectly, yet puddle fuel in the ports that was visible with a long reach bore scope down the intake runners, with the engine hot. During the testing the lab does not use hot fuel to test the injectors, nor do they have them fitted to a hot engine, in an engine bay that averages 140+ degrees F. The lab tests are done at ambient temperature.
This is why injector cleaning, and testing means nothing to me, and hasn't since these discoveries, which we now see all the time.
Agree,, Cleaning the injectors wont bring a worn out one back, but if you have a rig that does not get used a lot,, "hanger queen"
having the injectors cleaned does help avoid varnish buildup and fuel sludge clogging it,, my theory and its not specific to
Porsche in the least is that a cleaning every other year and new maybe every 80 to 100 K will give you the best overall performance,
I've had enough brand new injectors that were DOA that I'm as concerned about where they are made, and their manufacturing
as I am whether they are brand new. Add yea if you take apart an injector,, you can see quickly that a true full rebuild ain't very likely..
They just are not made to come apart.. I have dismantled the early fat body EV-1 injectors and reassembled them, but that
was young me where time was free and money short..
I use a injection cleaner consistently,, I try and put it in the last tank before an oil change..
And do the change when the tank is almost empty.. I use techron for the most part.
On the road race cars I've worked,, we send the injectors out every season..
over the winter then pickle them with a light oil like a marvel or a marine fogging oil.
Of course we also have 2 or three sets in the tool box..
For the mechanical injection on the sprint cars, they are simple and get cleaned between
each race weekend.. Methanol is just so aggressive your in trouble if they sit..
I think in similar vein and practice the same. I do have very intermitant stumble of one or 2 random cylinders at idle,
I don't see anything on scans, so I need get out the Durametric and see if I see anything.
(I might need help
but when I get some time..
Idle is sometimes unstable now and sometimes has a mini backfire . Any opinions would be much appreciated!
Thankyou
https://youtube.com/shorts/9_utLacn6_I?si=hufx9hiMpXAfjXb9
Can�t remember if I changed the coil packs at some point . I changed the spark plugs probably 2k miles ago. Sometimes the car is left over a month without using it; obviously every time before starting it again I try not to push it and leave it there warming up making sure everything is as it should be. IMS was done at 78 k miles and currently has 98 k miles. I�m worried there�s a scoring on one cylinder I guess I�ll have to use a endoscope to see what�s going on .. There�s 2 things that have my head questioning me if it�s related or not one being the clutch release bearing because not long ago it started to make a heavy tick noise different from what you hear on video after riding and car hot sound is audible when clutch is released on idle, but if I engage the clutch sound (clack,clack) goes away . Second thing is the fuel filter I�m pretty sure that has never been done; making one injector to stick and give a little tick, hickup and misfire . But in other hand what we all worry about is if there�s a scoring on a cylinder ? Or probably a lifter or timing chain tensioner (many factors) that�s why I�m here 😌 to figure out with you experts to help me out based on your experiences what should I do first ? I guess I shouldn�t drive the car cause it�ll make it worst . If I drop the oil with a bore scored cilinder should I see small shavings ?
Thanks you and sorry for my English .
Car is located in Nicaragua
You should drain the oil in to a perfectly clean pan and you might see a bit of metal with any motor,..
But to tell for sure the sump has to come off and do a bore scope... "Its the best way to be sure"
If you have changed the oil and don't have weepy injectors your odds go much lower down on odd of scoring..
Leaky injectors cause bore scoring in anything not just porsches.. The Boxer engine is just more sensitive to it.
DONT let a 996 sit and idle to warm up.. Start it, let it smooth out then drive away gently staying under 3000 rpm till it hits 180F
If you let them idle it takes too long to heat up the pistons, oil etc. .
If available in your area We have a product called Sea-Foam that is a marine engine fuel treatment. A half can in a fresh full tank of gas goes a long way to getting the varnish out of injectors. It forms when gas and oxygen meet without spark and sit around.. I use it in the last two tanks before I change the oil.
"
If you let them idle it takes too long to heat up the pistons, oil etc."
I was told that Its not the time to heat up, it's the amount of fuel to air mixture. Just sitting at idle when the engine is cold, doesn't that mean more fuel that washing the cylinders? Also known as running rich...
https://mechanics.stackexchange.com/...or%20starting.
The unburnt fuel washes the cylinders, preventing proper lube, and this results in more wear. ie. Bore scoring.
Get your car, any
road
car, moving once you've started it. At least you're getting some value for your money. I had neighbors who come out, or use remote start, and then have breakfast indoors with the truck running. In NC. It's not even below 30...Sigh. There's a lot wrong with that, but stupid is as stupid does. I'm not the enviro cops, so you know, live and let live. I believe that here in Canada, for years, most parking lots are no idle zones. I see signs all the time attempting to enforce that. But I've seen 1 LEO since moving back, and that one was parked at the digby RCMP. It's the wild West out there. Given the scarcity of law enforcement, I would imagine no idle laws are pretty dang low on the list of priorities. I'm rambling again. It's 'retiree syndrome' 💯🇨🇦❤️
LMAO...no idle zones....That's a new one on me...never heard of that..Thank you !!!
Here in Bama we have a lot of "no wake zones" on the lakes near Marina's .docks, but I can't imagine them ever putting no idle signs in parking lots...
I agree There are a ton of reasons NOT to idle a 996 to warm it up.. And almost no reason to do it.
Fueling, Engine warmup all part of a circle of proper care.. If your pistons don't get heat in them they don't
center and seal in the bore as well, this aggravates the fuel collecting at the bottom and soaking the lower side rings .
With a bit of RPM and load it helps keep the chambers from loading up till the heat comes in to help/
The nice smooth drive-away prevents many issues, and causes none.
Boxer engines usually like a hot turn off (Don't let them just sit and idle then turn off, light uptic in rpm to maybe 1500 then cut the ignition.) and a warm start. (Start and drive away slow)
In the ones i've played with, any boxer with a higher performance envelope has some issues with rich at idle. (I started on Bugs, subaru's moved on to a 69 911, and now the 996..)
Hard to make them pull hard at the top end and stay lean at the bottom.
I am always amazed at the amount of analyzing, conjecturing and hypothesizing that occurs on this forum when it comes to how things should be done right VS wrong with these cars.
I guess part of it is the type of owner - I have met many a super fastidious and **** retentive Porsche owners in my time, more than any other enthusiast group.
That said, I am glad I have "
Learned to Stop Worrying and Love the Bomb"
to borrow a famous phrase. I just enjoy my car, knowing it might blow up tomorrow, or it might last 30 more years.
Agreed. From now on i plan to do the following...
1. Never change my oil ever again.
2. Put back in my original imsb, fuel injectors, coils, spark plugs, water pump and failed aos from when I bought the car in 2002.
3. Everyday this winter in Chicago, i plan on starting the car and running it for 30 minutes in my driveway before I drive 1 mile to the grocery store.
4. Lastly, I am going to also go back to my original stock sump and reduce the amount of oil from full to a quart low on the indicator and then put on a set of Hoosiers and go the track to see if I can best my lap times.
There are some no idle zones, most commonly in places near building air intakes. Most famous was ambulances at a local hospital. Building designers put the building air intakes next to the ramps, where ambulances sat and idled endlessly, essentially gassing everyone in the building. Case of Dumb and Dumber if ever there was one. Most LEOs in your area damage, are busy with illegal fishing disputes
Respectfully, I would replace item 3 with �drive it like you stole it� because starting a cold engine in the winter is best warmed up by WOT to get heat in the cylinders as fast as possible.
Truer words have never been spoken !!.... But I must add to do your due diligence first, then "Learn to Stop Worrying and Love the Bomb"...
I remember when FoMoCo was sponsoring my race car that I had developed to 5X the OEM HP @ 12K RPM and setting IHRA records, after doing all my due diligence and a few small failures along the way, I had to learn to run the engine like " FoMoCo was going to pay me $1Mill if I could blow it up" ..of course they weren't going to pay me a $mill if my engine blew, but I had to tell myself that to keep from worrying about the "what if's"..and to push the envelope...being the Driver and Engine builder both makes that very difficult....When I was driving the Marshalls Race Car, I was the Driver Only, I wasn't allowed to work on or worry about the engine...That made running the engine to the limit easy peasy...
Also since it has been hypothesized that silicone particles will break off and can rub up and down the cylinders breaking off more particles, and since we know that a cold piston has the most clearance between the piston and cylinder walls, I tend to take my m96 to a fairly high RPM 1 Time in second gear BEFORE the engine is fully warmed up..just to release any particles that may have broken off, before the piston heats up and decreases the clearance to a point that a particle will get trapped and cause damage...
This is not a habit I just started due to over-analyzing the M96, I have always done this ( mostly for fun). I have always started my engines and drove away slowly getting everything coated with oil and a little bit of temperature in the oil, then taken the engine in second gear to a full throttle high RPM pull takes about 3 seconds,( if it is an engine I didn't build myself that I suspect may be a bit too tight), then I let it warm up the rest of the way slowly before any prolonged full throttle high RPM pulls. 140K miles on my M96 and I bet there is still plenty of silicone particles on the cylinders, and I bet there is not enough of them that have came off to even catch a fingernail...Not like the engines of the past where at 100k miles there is a big "ring ridge" at the top of each cylinder, this was expected on ALL engines in the past..
I was working on a 8N tractor... and we wanted to put in new pistons... Found one totally on accident at a flee market.. Ridge was .015 we ended up .20 over to get pistons with rings..
This is a source reference. Confirm exact model applicability in the original material.
