Problems after manifold change.

[vw_john 10]

Got a 4-2-1 manifold put on my G60 yesterday, and when I picked it up everything was fine, although when I went back out to drive it a few hours later it would start fine, then after about 5 seconds the revs started to drop and then it just cuts out alltogether.

thought it might have been a cold start issue but it started fine this morning.

Also the guy said that my lambda wiring was f*cked and he fixed that.

although the car is running much faster now, it seems to be running richer than before.

Any thoughts on the matter anyone?

Cheers,

John

[Album56 0]

What makes you think its running richer? How old is the lambda probe? If its running well & the starting problem doesnt re-occur I wouldnt worry about it, might just have been the ECU getting used to having a working lambda again!!

Mick

[vw_john 10]

I know its running richer because the exhaust coked up after a 10 minuite run, quite thickly aswell! and as far as im aware it could be the original.

i'll keep an eye out for it happening again, but even when i tried to stabilise the revs with the accelerator you could see the revs dropping.

suppose it could be the ECU settling in, although i thought that without a lambda the car would run like horse****?

cheers

[JMC 0]

Not necessarily, it used to be relatively common practise to run G60's without the lambda at all. If it has been mapped not working and then you reconnect it it could affect the fuelling. Try disconnecting the lambda and seeing how it runs - if its back to how it was before, problem solved.

[vw_john 10]

I recently had a new chip JMR, so it wouldn't be the mapping. when its dying, it sounds like its backfiring through the inlet. could the timing be out? the timing was only set by hand after the belt change.

[JMC 0]

Could be. How was the map done - if a map was chosen to enable the car to drive well while the lambda wasn't working, and then you reconnected the lambda, it will effect the fuelling. Also check the usuals (boost pipe to ECU from throttle body - was that disconnected when yor manifold was changed, is it now on the right outlet from the TB, any splits in the ECU pipe, do you still have the carbon cannister - any splits in that piping, blue temp sensor - is that working right).

[vw_john 10]

Map was a SNS chip bought from another member on here, so I'm assuming its using the lambda as I wasn't told differently.

checked all the pipes and unplugged the blue sender and it wouldnt actually fire... also i have noticed the engine is running cooler than usual, a sign of a retarded ignition timing as well as the rich exhaust and the backfiring though the manifold. Cant understand how changing the manifold would have done this though. My mates coming over tonight to ajust the timing properly so i'll see how that goes!