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YOUR RESEARCHGoing to Put in Rebuilt Injectors in my Motor
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Always appreciate Jakes expert opinion but lots of fuel injectors get professionally cleaned, balanced and flow tested and reused.
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I'm planning to have the coil packs replaced next.
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Suggestion
It's not worth it to me to put used/cleaned/qualified/rebuilt/(you choose which word you like best) at the chance that they might leak fuel into the cylinders washing the oil film off and possibly creating a long term engine fatal problem.
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Sure they sprayed fine, made great power, and solved misfire issues.
I've owned my car for something like 4 years now? Maybe it's been 3 years. It now has 50K miles, bought it with 34K miles as I recall.
Anyway, on one of my oil analysis, it had a very high fuel level in it......and that went away for all other analyses. But I do get soot on the right hand tail pipe. I've noticed that for at least this year, and I did buy the Joe Gibbs injector cleaner and put it in twice.
But reading Jake's posts recently, I'm just going to replace the injectors. I just bought a set of used injectors and my plan is to send them off to be rebuilt so I don't have to wait for my injectors to rebuilt after I pull them as I don't really have a place to leave my car for a week after pulling them, would rather just do it all at once. Rockauto has the service for $29.79 each:
https://www.rockauto.com/en/catalog/...+injector,6224
I bought the injectors off ebay for $75. Maybe once I am done with mine, somebody else could buy them from me if they wanted to do the same.
Figure this is a cheap investment of $180 for the rebuild and $75 for the injectors. And I like working on the car. Figure I'll be swearing a bit but it will be fun.
I've been thinking about replacing my injectors, or at least buying some to have on hand in case mine start to leak.
Warehouse33 sells 6 brand new Bosch injectors for the later 996.2 for just $174.04 (with the Rennlist discount)
That's where I'm planning to get them.
I see warehouse 33 doesn't offer them (I'm sure he could get them), but does offer the rebuild service from the same place that I posted above.....$41 each plus a $50 core charge.....or I'm sure you could send Jason the injectors and for $41 each get them rebuilt. The 3.4 injectors are about $190 each new!
I wonder why 996.2 injectors are $32 and 996.1 are $190.
I'm pretty sure Warehouse33 said their 996.2 injectors were brand new.
I'll have to double check before ordering.
I'd want new and not rebuilt.
I checked and Pelican Parts sell Bosch for $36.
I'll have to check and see if they're new too.
If the prices are correct, that's an advantage for the 996.2.
That's because the 996.1 is MORE special than the 996.2. You guys with the .2 just don't get it!
I don't think getting the injectors rebuilt is a big deal.....it's just the way it is. I think they give you a report of what they found....for me, all that will matter is what is left as I am buying used for the rebuild.
Rebuilding the injectors will do nothing to the internals. A "rebuilt" injector is just cleaned, and has some new seals fitted to it. The issues we are seeing are mechanical wear to the injector internals.
Only use NEW fuel injectors. The "rebuilt" ones you are buying may be worse than what you already have. Also, do not use an injector "rebuilt" by Python injection!
Rebuilt injectors get flow test to confirm spray patterns are correct.
Always appreciate Jakes expert opinion but lots of fuel injectors get professionally cleaned, balanced and flow tested and reused.
Of course, if money is no object buy new. But to say after your injectors are professionally cleaned, balanced and tested that they might be worse than before is less than honest.
I have tried every brand of rebuilt injector. We have also had local shops specializing with injectors work with them. The results have never been the same as a new injector. We've tested them back to back, and I've even ran tests where 1 bank of the engine has new injectors, and the other has rebuilt. The differences in fuel trim were notable, as well as the rough running index on each bank.
The bigger issue with rebuilt injectors lies in the fluid that was used to clean them, and how long they have been on the shelf. As part of what we do, we work with wholesalers of parts that are having issues with products. A couple of years ago one company lost a lot of money selling rebuilt injectors due to warranty issues. I was asked to figure out the issue and it was determined that the fluid that was being used had a shelf life in the injector of 30 days, after that period it would actually begin to corrode the injector internally.
That said, cleaning and "rebuilding" injectors is done in a lab environment. The injector is being tested in a perfect scenario. Put that perfect injector on a hot engine that has just been shut down, and see if it will hold 60 PSI of dead headed fuel pressure without bleeding down overnight without puddling fuel in the intake ports and cylinders that have open intake valves. Give it a shot. Injectors have been fighting us for 5 years, and when I recommend to you to replace them with new units, this all comes from direct experience, pain, and suffering.
Jake is right. You can not rebuild these and most fuel injectors from the last 25+ years. Physically not possible! They are "refurbished" by cleaning them (internally and eternally), then new external hardware is put on (pintle cap and O rings) and are then painted to look new. The internal moving parts are just as worn as then were before. If a company uses the word rebuilt, they are lying. Yes, most flow test them and then they take the 6 closest flowing injectors and send them to you as a set. Often this means that these injectors came form different engines. You have no idea what you are getting other than they are a "flow matched" set of old injectors that look new.
I've run into problems using rebuilt injectors in BMW engines.
Sure they sprayed fine, made great power, and solved misfire issues.
But they also leaked while setting.
They leaked up to the point of hydro-locking engines that sat very long.
Now I only use new injectors, especially in anything that is not daily driven.
Yep, what he said.
Which is THE problem we are trying to avoid. Fuel is solvent, puddling that up in the bottom of a cylinder leads to wear, and fuel intrusion. I have stories about this that would go on for days, including a paid technical consultation for a supplier of engines that had a dozen issues with new engines after the old engine had failed from bore scoring. The replacement engines started showing odd symptoms upon installation, and that was traced back to the same cylinders that failed previously. Luckily the core engines went through a photo documented teardown. The common denominator was the fuel injectors remained in their same locations, feeding the same cylinders with both engines. This was as conclusive as it gets, and well documented.
Why not just use the 996.2 injectors? The 996.1 injectors are EV-1 (0280150470) and flow 229cc/min, the 996.2 EV-6 (0280156053) flow 249cc/min that's a difference of just 9%. And if using Ethanol laced fuel (E10),it requires 6.3% more fuel than pure petrol, it will be closer to Lambda 1 (0 trim) than if using the EV-1 stock injectors and pure petrol.
Usually I see trims running +5-+6 % when running Ethanol laced fuel. The DME can adjust +- 10% LTFT and =- 10% STFT and will set CEL if a +- 25% is reached.
The EV-6 and EV-1 are the same length, connector, and o-ring size and Ohm (12).. The EV-6 has a better spray pattern and runs cooler.
The 0280156053 flows only 20cc/min more ( 249cc/min vs 229cc/min) than the 0280150470 and would even be better suited for E10 on the 3.4 engine.
Since the price is SO much different, seems putting EV-6's in the 3.4 would be worth it, I'm sure Jake has done this, comments Jake?
The 3.4 doesn't suffer from bore scoring as much as it's big brothers, but uneven or leaking injectors can certainly cause this issue.
That 996.2 injector 0280156053 249cc/min is also used in the 2.7 and 3.2 986 from 01+
Due to power output of our engines we generally use an aftermarket injector for a different application..
BUT when an early engine needs new injectors we do replace them as you mention. One mod is required to make the injectors fit the early style fuel rail/ clip. l�ll do a Rennvision video on that next week for you guys. It takes 5 minutes per injector
Jake's, thanks so much about saying that the 996.2 injectors would work with a modification. I would rather have new and truly appreciate you making a video on how to modify him to go into the fuel rail.
I don�t know why anyone thinks it�s a good idea to argue with JR about Porsche engines. It�d be like me arguing over the color of the moon with Neil Armstrong.
Now I�m just some knucklehead that mostly has rebuilt Ford small blocks but I love EFI. Ford�s EFI systems were originally based on Bosch designs. I read Bosch�s first EFI book back in college. Ford�s first mutiport EFI systems used Bosch EV1 injectors with EV1 being the electric connector. These were the old style single port one o ring, pintle cap having Bosch injectors with different colors being different flow rates. I have a handy dandy sheet that tells me flow rates, how much power you can support and at what duty cycle. EV6 injectors have different connectors and have 4 spray holes in the end for a better pattern and atomization.
I seriously doubt Porsche made EV1 or EV6 injectors with different plugs. I know Ford sells adapters for EV1 harnesses to use newer EV6 injectors. I also know you can get generic (read chinese) new style injectirs with EV1 connectors on them.
EV1 refers to the old Motronic connector and EV6 is a uscar connector. You can get adapters to upgrade EV1 to EV6. No one in their right mind would go back to EV1 from EV6 though.
As for cleaning injectors, I suspect Jake is right that they will leak after shutoff. New injectors are better. Heck I�m putting new generic injectors on my POS Ford for the $2k challenge. I won�t even used old injectors on that project.
Now after reading this I know to look for Bosch EV6s of a certain flow rate. I just need to know the spec fuel pressure for the flow rate. I bet I can find them cheaper.
Both the EV-1 and EV-6 mentioned in my post use the Bosch Jetronic/Minitimer connector , commonly referred to as just the EV-1 style connector.(not the USCAR connector knucklehead
)
EV-1, EV-6 and EV-14 are Bosch injector "body" styles, not connector types.
Bosch even makes the EV-14 in the "standard " length ( EV-1 replacement)with flow rates up to 1000cc/min with the "EV-1 style Bosch Jetronic/Minitimer connector."
BTW the flow rate is 3 Bar for these specs.
I'm putting new in mine. They aren't that expensive if you don't buy from Porsche! It's not worth it to me to put used/cleaned/qualified/rebuilt/(you choose which word you like best) at the chance that they might leak fuel into the cylinders washing the oil film off and possibly creating a long term engine fatal problem. That's just my choice...to each their own.
Agree. Well, questioning might be OK if one is seeking to understand.
But Mr. 996AE, maybe apologize for coming across as an accusatory tone?
I mean Jake has nothing to gain from his post, and I think his credibility has more than proven himself. You can have your opinion - and quite frankly, your experience does count and is of value. I think we just need to change how we come across.
The truth is, I, too, have countless examples of rebuilt auto parts being worse off than the used part I picked up at the junkyard.
Mine is an MK-II 2005 C4S. I told the mechanic new, no rebuilt, He will confirm prior to ordering. Swear I saw a post above that Pelican Bosch are new?? Maybe it was WH33. Maybe both.
My issue is your blanket statement. Rebuilt, balance, tested can be worse.
Jakes quote.
The "rebuilt" ones you are buying may be worse than what you already have.
Not trying to pick a fight with Jake, just not a fan of blanket statements.
You are correct sir.
Came off harsh.
Less than honest inappropriate.
Assuming every 996 owner is rich and can afford to pay for new parts and making blanket statements that your rebuilt, balanced and spray pattern tested injectors by a reputable company maybe worse than before (you paid to have them rebuild) is a pretty bold statement condemning every rebuilder of injectors.
Again, not every Porsche owner can afford to replace injectors. Many will need to rebuild and take their chance.
I would have thought the 996.2 injectors would be a "drop-in" replacement. They are the same length, connector, use the same o-rings on each end, same safety clip. I wonder if he was thinking of the larger "aftermarket" injectors he is using on the big bore engines? I can't think of any trick or mod that would need to be done. I guess we will wait and see...
I have some of each 996.1 and 996.2 injectors , but only the 996.1 are out on the shelf and have the fuel rail with them...They each have a index notch and a groove for the safety clip, but I remember them being the same...
The "rebuilt" ones you are buying may be worse than what you already have.
YES!
The point I poorly attempted to make is a professional, good reputation shop rebuilds, balance, spray pattern tested injector "maybe" worse is a bold statement even from the God of Porsche hard to swallow.
Thank you for the clarification.
I just looked up injectors on design911.co.uk put in my car details and it's coming up with a Bosch injector �75 GBP
99660612001 is part number , not sure if this is the mk2 injector as mk1 is superseded or could be a good deal!!
Anyone know if this is the original mk1 part number??
A thought on this. So the theory is that a leaking injector might pool gas in the bottom of a cylinder and wash away the lubricant, causing wear on the next start. Makes sense.
But, isn't there a stereotypical failure mode, where the right side cylinder bank is much more likely to be bore-scored? Surely if an injector failure causes the failure, we would see a randomly distributed set of cylinders affected and not usually the right bank?
Again, the injectors and the issues they cause are just a contributing factor. it is not THE cause, but it damn sure aggravates the issue. Remember that we have not had a return type fuel system since 2001, so the dirtiest and most stale fuel collects on bank 2, which probably adds to the equation.
The sooty pipe isn't a result of the scoring, it is the precursor to the issue. We have found sooty pipes in situations where the bores have yet to score, where fuel was puddled in the cylinders and intake ports at tear down. Last year I had a car fight me hard, and it was a bazaar issue. The fuel pump relay would hang and make the fuel pump run about 20 seconds after the car was shut off. It had a constantly dead battery, and that was because the fuel pump was running till the battery died. Of course, once it lost power the relay unlatched, and the problem wasn't there agin till the car was shut down.. The engine would start up and blow fuel out the tailpipes. I finally caught this occurring as I walked by the car with my 6 year old daughter and she asked me what the sound was... That was the fuel pump, I could not hear it due to tinnitus from working turbine engines. Anyway, the DME needed reprogramming to solve that issue. It took me damn near a month to figure it out, and I may not have ever figured it out if it weren't for Ava.
Everyone is always looking for the ONE thing that causes these issues. You won't find it, because it doesn't exist. It's an equation.
Having wonky fuel atomization, and leaky injectors is promoting the rest of the equation.. What makes it worse is Porsche only had one part number for the pistons on both banks, and they have an offset machined into them. That offset is perfect for bank 1, and horrible for bank 2. The same holds true with the Cayenne that eats cylinders way worse than the M96.
At the end of the day the Lokasil process is hit or miss with QC, and for the majority of the life of these engines people were following a decal on the engine lid, and the owners manual when it came to oil service intervals. All of this and more is the equation that creates this problem. It's not one thing, with an M96 and any mode of failure it is really never ONE thing that leads to the broken hearts.
That said, there's no reason to settle for sooty pipes, if you have them, correct them.
I spoke about this on the other thread I started, but I recently had my coolant expansion tank replaced and a few days later, I'm getting a smoking tail pipe at start up and now misfires. My tailpipe on the driver's side has started to produce a soot type coating, but I figured that was normal for a 17 year old car. The certified installer of my IMS Solution said the coil packs passed pre-qual on the Durametric, but that he noticed that they had some minor cracking and I would need to plan for replacement.
When he bore scoped my cylinders, he said he noticed very minor scoring. He also said that it was a very early case of scoring and normal with the M96 engines. That was 6 months ago. Could it have progressed faster than expected because of problem you mentioned with injector leak and modern fuels? I'm planning to have the coil packs replaced next. What else should I be looking at as a preventive step? Thank you!
Basically, he said overall I had a good motor considering the age and miles. I'm sorry, maybe I'm not relaying it clearly what he was explaining to me. But basically the cylinder bores had normal wear for a 17 year old M96 motor. It was the original factory motor.
Thanks for this interesting conversation!
Was already thinking of replacing injectors some time ago. Now nearing the 200.000km and finding a good deal on the Bosch EV-6 injectors the next service in two weeks the old ones will go out.
Sorry to dredge up an old-ish thread, but I'm wondering: Do the 996.2 injectors drop into the 996.1 rails? AFAIK JR never did a video on this and later Porschetech3 thought they would drop right in. Anybody know/confirm? Or know what the 5-minute modification is?
Still waiting for an injector to test on a .2 fuel rail...
On a side note, I've noticed bank one tailpipe is more sooty than bank 2 after my AOS swap. I need to figure this one out.
Yeah, I was waiting for the video to make it to the rennvision channel. It does appear FCP Euro has the
MK1 injectors
for a reasonable price. Their lifetime replacement makes this a pretty good deal.
All Rennvision videos are on hold until the editing of my M9X Engine Rebuilding step by step video is completed. So far we have 12 hours of edited material completed. This is a huge undertaking.
The replacement Mk2 injectors (some) do not have a deep enough groove for the Mk1 clips to retain them to the fuel rails.
Rennvision will return in February 2020.
Does anyone know about the quality of Standard/Intermotor brand parts? Rock Auto and a bunch of Ebay sellers list these
new injectors
for the 996.1 for around $65.
I would stick with NEW Bosch only.
Standard/Intermotor parts are OK, I've used their parts on other cars.
But I wouldn't use them for my 996's injectors.
Also beware of fake parts on eBay.
I went with Warehouse33 for my injectors.
https://www.warehouse33auto.com/
They had the best prices, and I trust they're real from them.
The boxes they come in have a hologram sticker with serial number which you can check on Bosch's website.
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