ECU problem at WOT.

[kamotors]

Okay for a while I've had a problem with the ECU kinda de-tuning the car, it makes it so the car hesitates when giving it WOT from a stop, If I reset the battery the problem is fixed for about 2 days. I kept on buying and trying new things and resettings the ECU and thinking that I fixed it only to have it come back a day later. Well today I noticed if I give almost full throttle(maybe 3/4) the car takes off really good, but if I floor it, it bogs until about 2000rpms and then takes off like normal. My O2 sensor is about 1 year old, i get no CEL and other than this the car is getting great gas mileage and idles almost perfect.

anyone know what would cause hesitation from a standing take off at WOT but not at 3/4 and if the ECU is reset it takes off great?

[kamotors]

okay I adjusted the TPS, it was off by maybe a mm. I adjusted it so when the throttle closes it clicks, car seems to run a little better but not much of a difference.

[kamotors]

I did some more tinkering around, the engine was cold when i did this, but touching the AFM flap makes the RPMs drop, removing the oil cap changes nothing. when the engine is cold the low RPM bog is not really their, its only when the car warms up. is the car running lean?

[vr2jetta]

When you touch the flap it makes the DME think the car is getting more air, causing it to feed more fuel to the motor, not surprising me that it makes it bog down. Did you check the full throttle switch? Did you do a stomp check to see if there is any stored codes in the DME? Did you test the AFM?

[kamotors]

When you touch the flap it makes the DME think the car is getting more air, causing it to feed more fuel to the motor, not surprising me that it makes it bog down. Did you check the full throttle switch? Did you do a stomp check to see if there is any stored codes in the DME? Did you test the AFM?

I re-adjusted the TPS and it seems to be working fine, the AFM flap moves smoothly, and when the car is cold, throttle response seems to be not so bad. when my ECU is learning it sets off the 1222 code but that is because the car has an 19lb injectors,M30 afm, and Mark d 19lb injector chip. after 1 day of driving their are no more CELs.

[kamotors]

FIXED!!for now, I'm guessing it had something to do with the header install, as soon as I got the headers I noticed than the car was not getting CEL anymore for running rich, I guess it got to the point of making the car run lean. so today I changed the settings on the M30 afm wheels, and normally this made the car have a poor idle,run rich,and throw CELs, but now the car started right up like nothing happened, idled super smooth, no CEL code at all, and ALL my bottom end power is back:) the car can spin the tires again:)

[kamotors]

well the problem came back, and when I punch the throttle the AFM door flings OPEN and makes a really loud clank noise, so I decided to purchase the Miller MAF kit for $300, then I plan to sell my current Mark D chip so I will only be in it about $130 which isn't bad and I don't have to worry about getting another bad AFM.

[nando]

M30 afm swap FTL

[kamotors]

M30 afm swap FTL

agreed