Generally how long should it take for the ecu to calibrate closed loop fuel trims after disconnecting the battery? And what are the procedures for doing so? I heard it needs 5-10 hot/cold cycles and i heard i just need to drive it for about 90 miles.

 

LTFT adjust every 5 minutes, the standard thing to do is take a 20+ minute drive with a steady state throttle for the best accuracy.

STFT constantly adjust during idle.

You can disconnect the battery for a couple of minutes and it should reset. Anymore info you'd like to give us so we can help you better?

 

Well my throttle body plate bent and during troubleshooting and searching for the culprit the battery at one point was disconnected. The 65mm throttle body was replaced with another 65mm throttle body. Now the car won't hold idle. Have to keep feeding it gas. I've had this before but after a few cold/hot cycles the problem would correct itself. But now I'm 40 miles into it with numerous cycles the problem remains.

 

I'm starting to think that maybe the seller of the throttle body messed with the idle screw.

 

I'm having cold start idle issues with my evo also I've tried adjusting the biss screw but i didn't even see the idle right with i was adjusting it. Anyone have any other ideas to keep the car from stalling at cold start and it sounds like its chugging and the wideband is reading real lean so idk if that's causing the chugging sound due to lack of fuel

 

Ch53 let us know the results of adjusting the biss.

mp evo what are your mods and fuel?

 

my fuel mods are BR double pumper, agency power fuel rail with a stock regulator, fic 2150's. the motor is a buschur 2.0 block with a stage 3 head and buschur bf cams. idk the lift or anything on cams but i'm trying to figure out why it has a real rough cold start and it sounds like it's misfiring but the wideband is lean so idk if thats the reason