i got a 07 5.4 with cat back duals and cai and tbs ( i know waste of money ) and an edge evo on level 2 tow tune, well the other day it got pretty hot out and i was in crawling stop and go traffic for like almost two hours and the engine and tranny natrually got really heated up, and i got the codes for banks 1 and 2 being to lean, now i'm wondering and hoping that it was because the trucks pcm leaned itself out because it was so hot, but i do know that the evo is designed for stock trucks and with mods it can make it run lean and do damage, i've cleared the codes the same day but the next day ( alot cooler out by the way ) i ran a diagnostic check and the codes were back, so any advice on this wether it's something i can do like timing advance or decrease or anything else i can do to prevent this or if it wa just because it was real hot that day would be greatly appreciated and would give me peace of mind cuz i'm in the marine corps and the don't pay that great so ruining my truck is not on my list of things to do. thanks to all that have input.

 

Try cleaning your mass air flow sensor. It may be caused by your CAI

 

I didn't even think of that, i will try that as soon as it stops raining out thanks alot i hope it works

 

If you have the tools to do so, pull your front O2 sensors and test them. More times than not a bank 1/2 code is the sign of failing o2 sensors. Especially something just out of the blue like this. If you have had those mods for a while and just now you start to get a code, start there first.

I come to the conclusion of this because you described whats called a closed loop driving situation(meaning part throttle or idling). Your PCM can compensate for quite a bit in closed loop and really wont ever go lean/rich given your not changing things out like injectors or fuel pumps without letting the PCM know about it.

If your getting this code because you went WOT, then its a whole different ball game and you need to add some fuel with your tuner. In open loop the computer is having to do a lot of guess work and cant compensate for things as well.

 

I think the O2 Sensor sounds right, but on a side note....shouldnt the PCM deliver more gas if the engine starts to heat up, a lean condition will cause overheating, and a rich condition more than likely would not do this. I only say this because we race dirt late models, and you want to find that perfect spot where youre rich enough to keep the motor cool but on restarts you arent going to bog/flood the motor when you punch it.

 

thanks alot guys i'll def try cleaning the maf and look at the o2 sensors