Ex-Bitten Hero

Had this a couple of times now.

If I leave it idling (from hot or cold) for about 30 mins (like the other day when the anti-carjack thing locked me out ), then very small amounts of white smoke start coming out of the exhaust. If I then drive away, it starts knocking badly (like detting perhaps?) and a fair mist of white smoke comes out the back as I do so . Obviously under these conditions I'm driving like a granny (low throttle, <3000rpm) and it clears over a few minutes of driving and everything's fine again.

My theory is that there's heat soak in the engine bay (cooling fan works fine though and temperature gauge shows spot on in the centre) and this is making something unhappy. For instance, if the intercooler was getting hot and actually heating air coming into the system, this would result in relatively high inlet temperatures - but would they be high enough to cause det? And why would this cause white smoke to come out the back?

Another possibility is it's only running on 3 cylinders for this time (perhaps explains knocking noise) but then I would have thought it would be blue smoke (unburnt fuel) coming through?

I've checked all fluids and everything's fine - it's not burning oil (at least not at any appreciable rate).

Any suggestions? Has anyone else had this? Apart from this my car runs like a dream, and was only serviced 1500 miles ago...

Ta in advance
Richard

(MY00 PPP and better air filter, no other mods other than boost gauge)

[Edited by Ex-Bitten Hero - 6/5/2002 12:49:21 PM]

Ex-Bitten Hero

Come on guys! Someone must have an idea!

Please?

Richard

[Edited by Ex-Bitten Hero - 6/6/2002 4:42:56 PM]

Diablo

Hmm..white smoke suggest water.

Water fouling plug (s) could cause miss fire - hence the 3 cylinder issue.

Knocking could be slap or detting, would need to hear it.

My guess would be head gasket failure.

But its only a guess.

Hope you get it fixed.

D

DaveD

iTrader: (2)

Head gasket failure would result in the engine getting very hot & big clouds of white steam - doesn't sound like the cause.

White smoke out the exhaust could well be unburnt fuel. Sounds like for some reason one of the cylinders isn't firing. Could be break-down of one of the plugs/HT leads? (these would be cooled by under-bonnet air when driving along normally)

Ex-Bitten Hero

Phew, thanks Dave - that's what I thought. It's definitely smoke not steam. Would unburnt fuel be white or bluey though? I thought oil was white and fuel blue? But not sure...

Thanks for the ideas.... any more?

Cheers
Richard

planky

Oil blue,fuel is normally black/grey.water is white

[Edited by planky - 6/6/2002 10:47:23 PM]

WREXY

Have a listen to this sound file of piston slap provided by Alan Leslie, so that you can see if the noise you are hearing sounds anything like it.

http://homepage.ntlworld.com/alan.le...p%20(cold).mp3

Cheers,

Wrexy.

submannz

Turbo failure can also cause white smoke.

Fuel smoke can also be brown.

Ex-Bitten Hero

Thanks for the thoughts. I was wondering if it was a bit of oil getting in round the turbo casing or something I'll just keep an eye on oil levels etc for now, and not leave it idling.

Cheers
Richard