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Got my car back this afternoon from the mechanic. He didnt change the afm, basically gave it a check over, put it on the dyno, drove it round on the road a bit and said he couldnt fault it. Got it back on the highway and within 5 mins i had created a traffic jam! The problem is very easy to instigate, if i drive it gently and not on boost, all seems ok, if i give it some, say 1/2 bar or more, after i stop accelerating it basically looses all power, splutters, shudders i get very little response form the accelerator (if any) and if i fully remove my foot from the gas it will stall but i can keep it alive by pumping the accelerator, eventally it springs back into life as if nothing happeded. If i accelerate hard again same thing happens. Any ideas??

Cheers

Twitchy,

Sounds similar to a problem I had (and which we eventually fixed). Car would run like a dream and then, for no apparent reason, loose all power, survive a complete stall by pumping the accelerator, then after about 15-20 seconds, it would come good again and off we go. Kept happening at the most inappropriate times.

Same deal, we thought AFM, replace both (paid about $150 each second hand). No good. Changed fuel pump, checked wiring, relays, computer, CAS, spark advancer - basically everything you could think of. Mechanic would say - "I think we've got it now" after they road and dyno test - only to do it again on the way back to work.

ANYWAY... turned out to be the plug to the computer. It has a single bolt on the centre of the plug. As the car accelerates or brakes, the plug would rock - ever so slightly - and lose connection with the fuel pump pins. Used a bunch of zip ties to hold the plug firm on the edges - never had a problem since.

It's a long shot - but if it is the cause - you may not have thought to look at it.

Hope you get it fixed soon.

Cheers

Peter

ANYWAY... turned out to be the plug to the computer. It has a single bolt on the centre of the plug. As the car accelerates or brakes, the plug would rock - ever so slightly - and lose connection with the fuel pump pins.

Hi Peter;

that's a beauty, how did you manage to find it?

GTR 32,

I think it was when they were changing over the ECU (from Apexi back to stock back to Apexi) when they noticed the plug - which is actually more like a bar had a slight bow in it. I would have been stuffed otherwise - it had taken 3 weeks of trial and error, calling in auto electricians, 2 fuel pumps, etc, etc, etc when someone came across this.

At one stage, whilst at the mechanics, we couldn't start the car. Put a pressure gauge onto the fuel line and had zero pressure. Everyone stuffed around trying to work out why - no go. One of the guys leant up against the car - hey presto, full pressure.

Was driving us nuts.

Definitly worth a check if you experience any wierd stalling as described.

G'day Peter, very interesting reading your reply, sounds almost identical to my problem. I havnt heard back from the mechanic since i gave the car back to him last week (wednesday) so i gather he hasnt fixed it. First thing tomorrow i will ring him and let him know about your problem and solution. I have a feeling that it is an electrics problem due to some other strange things (electrical) that have happened in the past...he's not so sure though. I really appreciate your advice and will be sure to let you know the out come.

Cheers

Andrew

I didnt realise how lost i would feel without my car :rofl: i usually walk around with a big grin on my face, however since that fateful day last week i seemed to have lost such an expression :) (never thought i would feel like this about a car).

Edited by Twitchy
  • 2 weeks later...

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