Jcmotors406
What car (year/model)? Any mods (exhaust, downpipes, cats, tune, etc)?
They are just pending codes so technically not confirmed and could have been a weird state (common on any modern engine to sometimes get pending codes). I assume you didn’t get a check engine light?
Lean conditions are generally not a good thing, though it could be caused by aftermarket mods, or just a sensor misinterpretation since it’s just pending.
Normally I’d say clear them and see if it comes back. If it does, then more diagnostics will be required. Do you have any freeze frame data?
Thanks!
Z.
They are just pending codes so technically not confirmed and could have been a weird state (common on any modern engine to sometimes get pending codes). I assume you didn’t get a check engine light?
Lean conditions are generally not a good thing, though it could be caused by aftermarket mods, or just a sensor misinterpretation since it’s just pending.
Normally I’d say clear them and see if it comes back. If it does, then more diagnostics will be required. Do you have any freeze frame data?
Thanks!
Z.
Sorry for the late reply every one the McLaren is a 2017 570s it is bone stock besides driver mod lol.
For what it is worth these codes out of the MDS are labeled as such:
P2177 - Fuel System Adaptions (Multiplicative) :: Adaptive values reach the limit (bank 1) :: Max Fault
P2179 - Fuel System Adaptions (Multiplicative) :: Adaptive values reach the limit (bank 2) :: Max Fault
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Like many have mentioned before it is from a lean condition. It is generally triggered when Long Term Fuel Trims reach a value of 1.25 meaning the adaptive fueling process is adding an additional 25% fuel to the modeled feed forward tables in order for actual lambda to hit the target lambda value. Like mentioned above it is generally caused by an intake leak at idle or cruise (vacuum conditions / vehicle not under boost) The McLaren uses a hybrid system of MAF and speed density to calculate the air mass entering the cylinder. MAF is generally used during low air flow scenarios thus an air leak in the system can cause a lean condition under vacuum. If MAF is used under heavy load (it generally isn't in McLaren) it can also result in a rich condition unless the leak is post MAF but preturbo. That can result in a lean condition as well under heavy load.
Your scan tool should be able to tell you what your LTFT and STFT trims are. Or like someone else had mentioned, a snapshot will also give this info as STFT and LTFT is a standard PID required by OBDII standards.
Long story short, @zerokewl gave great advice to check for leaks, particularly in a bone stock car.
If you guys ever come across any codes that you need help deciphering, particularly McLaren specific codes, please feel free to shoot us an email. Info@M-Engineeing.us or Info@DynoSpectrum.com
P2177 - Fuel System Adaptions (Multiplicative) :: Adaptive values reach the limit (bank 1) :: Max Fault
P2179 - Fuel System Adaptions (Multiplicative) :: Adaptive values reach the limit (bank 2) :: Max Fault
Like many have mentioned before it is from a lean condition. It is generally triggered when Long Term Fuel Trims reach a value of 1.25 meaning the adaptive fueling process is adding an additional 25% fuel to the modeled feed forward tables in order for actual lambda to hit the target lambda value. Like mentioned above it is generally caused by an intake leak at idle or cruise (vacuum conditions / vehicle not under boost) The McLaren uses a hybrid system of MAF and speed density to calculate the air mass entering the cylinder. MAF is generally used during low air flow scenarios thus an air leak in the system can cause a lean condition under vacuum. If MAF is used under heavy load (it generally isn't in McLaren) it can also result in a rich condition unless the leak is post MAF but preturbo. That can result in a lean condition as well under heavy load.
Your scan tool should be able to tell you what your LTFT and STFT trims are. Or like someone else had mentioned, a snapshot will also give this info as STFT and LTFT is a standard PID required by OBDII standards.
Long story short, @zerokewl gave great advice to check for leaks, particularly in a bone stock car.
If you guys ever come across any codes that you need help deciphering, particularly McLaren specific codes, please feel free to shoot us an email. Info@M-Engineeing.us or Info@DynoSpectrum.com
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