Problem:

From cold the engine will suddenly lose power only for a split second, jolt/judder, can stall(starts straight back up). It's worse in lower revs and/or when you brake or dip the clutch. It can just happen when driving in normal but when the engine gets warm it (hardly) happens. I've gone down the usuall route of changing sensors etc.

I've replaced -
Coolant Temp Switch
Stepper Motor - ICV
MAP
AIT
VSS
TPS
Plugs
Fuel Filter
Lambda Sensor - Apparently doesn't even come on for the first couple if minutes anyway.


The engine has been on a diagnostic computer and finds no faults. Apparently when he tried to do something with the ECU it went erratic. The engine has had a remap, he suggested reformatting the ECU and losing the remap to see if it's a ECU problem? I can't see it, why wouldn't it happen all the time and just whn it's cold?

Does anyone know if this could be a bad earth problem? Could it be Electrical? This all happened after 1 day after i bought the car, i know i should of taken it back but i thought it was an easy fix and i like the car P

The exhaust has a slight rasp which needs looking into but i think thats more Lambda related?

It seems to me whatever the problem is, when the car warms it sorta stops. I've spent a small fortune on sensors and garages and still have no clue what is wrong. I've read many threads on the site and tried many fixes. Someone out there must have had a similar problem and can point me in the right direction!!!!!!!!