R33 Gtr Overfueling/stalling Problem

[fomby639]

just had the car for 2 weeks and somthing has died, on start the car doest like to rev above 3000, if i try to rev it, it overfuels and dies. if i press and hold the throttle, the rpm will jump 500rpm and then it will gradually stall, if i keep stabing at the throttle it will cough and splutter but the revs build up over 2500-3000 and its fine. once the car is warm its fine for about 10-20 min of driving then it will start happening again but it will happen randomly, could happen 4-6 times every 300m or could happen once and then run for another 20 min with no problem. ive run a multimeter over the coolent temp, O2 sensors, AFM and TPS (throttle positon sensor), they all seem fine. ive ran the car and unpluged sensors (AFM's, TPS, O2 sensors, coolent temp) and pushed a few more but it doesnt have the same problem. ive read a few forums and all i can come up with is the ECU is gone, or there is a bad connection in the wiring. motor is mostly stock cept for cam gears, boost contoller. Has a Mines ECU so i can't run diagnostic's on the ECU. Anyone have any idea's? is there a cold start control valve on the r33 rb26?

[jjman]

do you know if the mines ecu was tuned specifically for that car in japan or if it is simply a mines ecu plugged into your car?

mines ecu's are notoriously dangerous to cars in australian conditions...

[fomby639]

not sure, i heard that mines ecu's are bad for aus hence why im going to a power fc as soon as possible, id say its a normal plug and play mines ecu, only other thing would be i changed the plugs and it started happening, the standard coilpacks look fairly heat effected, i put in new denso plugs, same as i ran on my old 33 gtst, i have new superspark coil packs that i plan to put in on the weekend, hope its as simple as that tho im doubtful...

Edited April 1, 2011 by fomby639

[levinboy]

maybe double check the spark plug gap??

[R31Nismoid]

Sounds like typical AFM issues.

Simply unplugging won't do anything. It's an intermittent error within the AFM itself.

Try swapping with a known working set. I'd say it'll be fine then.

Failing that, put a stock ECU in and see what happens.

[fomby639]

i kinda ruled out AFM because its not a limp mode problem, ive had that before, it def feels like a over fuel prob. should be getting a power fc very soon, if i cant fix it by then, should they be able to fault find while tuning?

[fomby639]

put my old plugs back in today, didnt miss a beat. the denso's i put in where the same as Hi Power Racing put in my 33 gtst when the power fc was installed and tuned. the denso's in the gtst where still going strong 18 months after the tune when i sold the car. thanks for your help and input guys.

[R31Nismoid]

i kinda ruled out AFM because its not a limp mode problem, ive had that before, it def feels like a over fuel prob. should be getting a power fc very soon, if i cant fix it by then, should they be able to fault find while tuning?

Intermittent AFM signal problems do not cause the car to go into limp home mode.