i have a 2003 evo and when i im parked and i acelerate the car, when it drops, the iddle go to low and the afr on my wide band goes to 8. for a few seconds,almost turning off the engine and it compensates and then i goes back in a perfect iddle and the mix on 14 as it should be. what can itr be?

 

what bov are you useing and is it recirculated

 

stock evo 9 one and istalled as stock goes.. recirculated

 

no ideAS?

 

Yesterday i change my mass air meter and no luck. Today i will try a new o2 bank one from another evo, also im getting rid of the egr to see if i get lucky.

 

Hard pipe intake????

 

The intake is rubber, perrin

 

Check your tune. Look at your FT and check your injector latencies.

 

TUNE IS STOCK. I REFALSH IT BACK TO STOCK. WHAT DO YOU MEAN FOR FT?
AND FOR LATENCY YOU MEAN InjPulseWidth ON THE EVOSCAN? THANKS

 

Are you using stock injectors?

 

FT = Fuel Trims you have LTFT and STFT
Long Term Fuel Trims
Short Term Fuel Trims
in evoscan your LTFT should be under +/- 5% the fuel trim is how much fuel your ecu is adding or removing in order to achieve 14.7 afr. when your stft is bouncing around like crazy the ecu attempts to stabilize the afr by making a long term change the ECUs LTFT which is what some refer to as "learning". by looking at your stft and ltft you can determine if the car is being under fueled or over fueled which could be your injector latencies or flow rate (in ecuflash) or a mechanical issue with the injectors.

 

stock injectors

 

KillaItalian904:

AT IDLE:
FuelTrim_Low FuelTrim_Mid FuelTrim_High
-3.429 -12.4496 .1008
STFT GOES FROM -4.6 TO 12

 

-12.4496 is not a great fuel trim but if i am reading this correctly 12.4496 is your fuel trim MID which has nothing to do with your idle, the fuel trim mid is only for cruising. your ltft low looks good it doesn't seem like its over fueling, seems like a mechanical issue to me but thats my humble opinion

 

How about the stft? Im guessing is a bad sensor somewhere