Thread: stumbling at low rpm

check knock sensor and line, i had the same issue stumbling on cold and that was the culprit

^^^ yeah tps should read well over 4-4.5v on WOT afaik.

Here's a question, will the check engine light on the dash ONLY come on if the ECU is in fact, throwing codes? Or does it not matter?

Did you check the TPS after its al warmed up? because cold start the throttle plate stays opened a bit more. I say, get her/him warm and then check your TPS. Ive been told this. Also this might help to reground the maf. I would do it even if you dont always need to. Just for a piece of mind

this is a old trouble shooting thread of mine, hopefully some of it can help http://www.sr20-forum.com/general-sr20/52291-acceleration-issue.html

i will go over it again but im kinda thinking its the iacv but not 100% its just getting annoying also the throttle response at the bottom end is really laggy all the time is it because its a heavy car? also my buddies b14 4 dr with the ve walks on me all day? the only difference is he has a 2.5" cat back with a can and im running stock?

I would ground the maf man jusr for starters. Check voltages on tps fuel injectors ect...

i just checked the tps and at closed throttle its .08 and open is 3.5 and wont budge from there?

closed says 0.2-0.8 and open should be between 3.5 and 4.5v so im in the range

My b14 has a ve with the jwt ecu, it does the exact same thing your car does and the reason is the ecu. I've swapped it for a factory ecu and the problem goes away entirely, but the car runs much better overall with the jwt ecu. Small price to pay considering once its warmed up its fine