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Thought I'd share my current situation to help people possibly not make the same (possible) mistake I made.
My ride is an '08 R52 S with 151k miles. Upgraded with 17% S.C + 2% crankshaft pulley, NGK plugs, 380ccs (Bosch 0280156063/62431, not JCW's Siemens). Also using the JCW factory tune (210JCW).
Car had been running quite excellent for at least 10k miles with above configuration, up until last week, when I had a meltdown on piston #1. The event happened while car was WOT and cold night (definitely pulling 17.5+ psi ... I got the "MAP high input" diag code).
Following some research, seems this event (maybe pre-ignition or detonation) was caused by a too lean mixture with highly compressed air, which in turn could have been by lack of fuel from #1 injector. Worth noting, I have never gotten any codes suggesting I was ever running with lean mixture. I've only gotten MAP high input on WOT (a fair number of times).
I'm currently still picking up facts to best determine how to avoid this in the future. I'm doing an engine swap, so I want to reduce the risk of this happening again. This is my list of data in case anyone is able to add to it. Much appreciated:
1) Stop driving at WOT
2) Running 19% effective may run close to the 380ccs fuel delivery. If my driving style is that of being WOT freely, maybe 17% (15%+2%) is best?
3) Some have said to go with bigger injectors if you go 19% effective. I need the car to remain California smog legal, so I need to keep the tune to factory tune (210JCW), so I need to stay at 380ccs...
4) Replace fuel pump filter, and possibly consider a higher flow fuel pump (?)
5) Stick to the JCW Siemens 380cc injectors because they are definitely not the same as the Bosch's when WOT (?)
You need to have it tuned on a dyno to check the afr's. I'll bet your air fuel at WOT your mixture needs to be richer under WOT.
Yeah, I'm using 210JCW tune ... cant deviate from that if I want the car to pass smog without interchanging DMEs (new California rule).
I've driven the car at WOT many times, gotten the MAP high input code many times, but have never gotten any codes for mixture too lean. Shouldn't I be getting them if that was the case?
I've driven the car at WOT many times, gotten the MAP high input code many times, but have never gotten any codes for mixture too lean. Shouldn't I be getting them if that was the case?
Just learned from Mod MINI YouTube channel that at WOT, DME doesn't take into account O2 readings and just dumps as much fuel as possible to the motor. This means at WOT, the DME cannot due lean/rich mixture readings ... that's why you may not get codes of a lean mixture at WOT...!
It detonated because it was always running lean at WOT since his tune is a stock JCW? Is this what happened?
So , the solution is to get an AFR gauge with a wide band sensor. And if it is running lean with the results of AFR , then custom tune by Adrian.
My question is this, how does California know that you have a custom tune during smog test if you just tweak AFR? I don't live in CA , thank goodness 😂
It detonated because it was always running lean at WOT since his tune is a stock JCW? Is this what happened?
So , the solution is to get an AFR gauge with a wide band sensor. And if it is running lean with the results of AFR , then custom tune by Adrian.
My question is this, how does California know that you have a custom tune during smog test if you just tweak AFR? I don't live in CA , thank goodness 😂
The BAR test equipment will pick up "many" computer changes. From what I was told, we can thank the Big truck guys for the increased overwatch. I was told by a test guy that because the truckers figured they could get away fuel changes to their trucks ECM's, they be alright. Somehow this got caught, and the test equipment changed to actually read what's in the computer mapping.
I don't know exactly...how...factual this all is, but the guy giving me a hard time about my JCW (freaking vacuum/boost gauge !) last year seemed pretty knowledgeable on the subject.
I wonder if changes "only" to the high rpm/boost areas of the fuel/timing maps could be changed without getting caught
After everything I've read so far, I'm considering following options:
1) Reduce to 15% pulley and minimize time I'm driving with WOT
2) Stay with 17%, but avoid going WOT when conditions lead to overboost (cold mornings/nights it seems). Maybe get the boost and AFR gauges as well.
--> I say this, because I seem to only ever get "MAP high input voltage" DTCs when WOT in the cold.
3) Stay with 17% but use bigger injectors and custom tune ... swap back to stock for smog checks.
I dislike #3 because of the inconvenience of it all, but at least #3 lets me drive without having to think twice about how much time I'm driving at WOT and burning my pistons.
The easiest solution for you is to get another ECU from Mrblah. He can clone your original ECU with vin. With the cloned ECU, ask Adrian to tweak it to your hearts content and play with WOT, of course with boost and AFR gauges. Now since you are in CA, during smog test, swap back to your original ECU. Max time swapping, less than 2 minutes.
The easiest solution for you is to get another ECU from Mrblah. He can clone your original ECU with vin. With the cloned ECU, ask Adrian to tweak it to your hearts content and play with WOT, of course with boost and AFR gauges. Now since you are in CA, during smog test, swap back to your original ECU. Max time swapping, less than 2 minutes.
Folks,
While beginning to start taking engine out, a barely small touch of the vacuum hose line to the fuel pressure regulator cracked. The tube was very brittle. Later on it even cracked closer to the supercharger ... so chances are this guy had a crack somewhere earlier ...
So that being said, some folks are saying that if the FPR vacuum line has a leak, then this can cause a lean condition at WOT. Others on the other hand say that the MINI FPR actually increases PSI on lack of vacuum (so it would be richer). Anyone would care to confirm what would the behavior be of the fuel pressure regulator at WOT if the vacuum line was leaking or missing?
Asking because, well, I'm trying to find root cause to my mishap.
Folks,
... some folks are saying that if the FPR vacuum line has a leak, then this can cause a lean condition at WOT. Others on the other hand say that the MINI FPR actually increases PSI on lack of vacuum (so it would be richer). Anyone would care to confirm what would the behavior be of the fuel pressure regulator at WOT if the vacuum line was leaking or missing?
Asking because, well, I'm trying to find root cause to my mishap.
Read some more online and I've come to learn that indeed, mixture will run lean if there's a vacuum leak at the AFR. ECU may adjust fuel delivery to attempt to fix the lean condition...
... But if the leak or failure of the vacuum line failed at WOT (when ECU cannot properly read for either rich/lean condition due to narrowband O2 sensor), then all bets are off!
Last edited by Eddie Vergara; Mar 11, 2023 at 03:08 PM.
Read some more online and I've come to learn that indeed, mixture will run lean if there's a vacuum leak at the AFR. ECU may adjust fuel delivery to attempt to fix the lean condition...
... But if the leak or failure of the vacuum line failed at WOT, then all bets are off!
Very sorry that you lost your motor!
When my FPR line came off, my WOT AFR went lean. It did not drive correctly, but having the air fuel gauge helped me trouble shoot the issue quickly. Personally, if I had done this, I'd do a new fuel pump, filter, brand new fuel pressure regulator line and get my injectors flow tested and cleaned before putting in a new motor as well as getting an A/F gauge.
Personally, if I had done this, I'd do a new fuel pump, filter, brand new fuel pressure regulator line and get my injectors flow tested and cleaned before putting in a new motor as well as getting an A/F gauge.
Yep, sounds like I may go exactly this route.
Mind sharing which gauge and wideband O2 sensor did you go with? Thx!!
Mind sharing which gauge and wideband O2 sensor did you go with? Thx!!
I've used a bunch, but I've had good results with the AEM UEGO. Try to get the one that's new - can't remember the model - but it uses a newer plug Bosch wideband sensor that's cheaper and more readily available.
Whatever you do, stay away from the Innovative ones, they ruin the sensors very quickly.
I've used a bunch, but I've had good results with the AEM UEGO. Try to get the one that's new - can't remember the model - but it uses a newer plug Bosch wideband sensor that's cheaper and more readily available.
Whatever you do, stay away from the Innovative ones, they ruin the sensors very quickly.
Thx, I'm in CA, so I'm trying to find a solution that won't muck around with my exhaust and keep my car street legal.
I'm currently researching the PLX wideband O2 solution which appears to provide a narrowband output as well so it can connect to the ECU. Curious if anyone has feedback on this?
Thx, I'm in CA, so I'm trying to find a solution that won't muck around with my exhaust and keep my car street legal.
I'm currently researching the PLX wideband O2 solution which appears to provide a narrowband output as well so it can connect to the ECU. Curious if anyone has feedback on this?
The UEGO will also output narrowband info to the ECU. If you do that, make sure that you're sharing the same ground as the ECU does as there can be some variance depending on where you wire the wideband. I still have a PLX that I first started using in 2006 and it's been bulletproof! Can't go wrong with them.
The UEGO will also output narrowband info to the ECU. If you do that, make sure that you're sharing the same ground as the ECU does as there can be some variance depending on where you wire the wideband. I still have a PLX that I first started using in 2006 and it's been bulletproof! Can't go wrong with them.
Thank you very much!
Aside from the instructions provided by PLX, do you have any referencing material for install, tips/hints on setting it up? Thanks!
It detonated because it was always running lean at WOT since his tune is a stock JCW? Is this what happened?
So , the solution is to get an AFR gauge with a wide band sensor. And if it is running lean with the results of AFR , then custom tune by Adrian.
My question is this, how does California know that you have a custom tune during smog test if you just tweak AFR? I don't live in CA , thank goodness 😂
OBD2 offers parameter IDs (PIDs) to enable diagnostics software (and this includes emissions test software) to obtain Calibration IDs and Calibration Verification Numbers. These can (will) show the engine controller flash image has been modified. Word is that once the image has been tampered with even if the factory image is put back in the Calibration IDs/Calibration Verification Numbers don't get reset.
At least one car maker I know of (and I suspect the majority do this) scans the ECU image and if it detects it has been changed/tampered with will log a proprietary OBD2 error code that can't be erased. When the vehicle is brought in to the service department and the diagnostics computer connected during its scan of the car's electronics it will read this code and this signals to the tech the engine controller image has been tampered with.
