Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[ScottieMV6]

Did use genuine gaskets, may have made a mistake as never done them before so it is possible, but no oil on the plug leads when I pulled them out.

The oil that came out at last oil change was very black - looked like it hadn't been done for some time but I have only ever done about 3000 miles in the car since I got it. Probably should have changed it sooner!

Not checked the coolant for smell of oil/petrol.

[ffcgary1]

Then the next step is to replace the ign leads as they could be fried. then dis pac

[ScottieMV6]

So will the misfire explain the clouds of white smoke out of the exhaust Gary?

[ScottieMV6]

I am at a total loss here. All the symptoms point towards HG failure but the readings don't confirm it.

Is there anything else anyone can think of that would give these symptoms?? :-/ :-/

[ffcgary1]

The mis fire will result in unburnt fuel. The white smoke maybe a sign of poor combustion ,ie missfire, as it is normal for a well tuned engine to produce some water  during the combustion cycle. if the engine is not getting hot enough to heat the ex systm then you may well get steam.

[biggsy]

I had a similar problem with my 2.5 cdx re the white smoke
had the egr valve tested by vx as they said this was culprit
however turned out ok ?? anyway long to short put plate where egr valve was replaced plugs (they where oily) RESULT no more white smoke  that was last year and about 11000 ago never looked back.

Re the plate my friend is with vauxhall this was his recomendation the reason being, no need for remap
as when vauxhall do the remap they (allegedly)charge you for a new egr valve which has been by passed by the remap anyway    haha. i also put a plate on my wifes astra both cars ok for emmisions at mot and run a lot better.
I mention all this so i dont get slagged for doing the plate and not the remap 

[Kevin Wood]

I am a bit troubled that one of the pots managed 19.5 BAR on the first attempt. The only way this can happen, IMHO, is if it was initially full of liquid which dissipated during the test.

Now, this could have been coolant from a breach in the HG, of course, but, whilst a compression check isn't necessarily conclusive, I tend to agree that those figures look too good for an engine that's blowing white smoke and missing as badly as you state.

What if that cylinder had a weeping fuel injector? If you've got fuel peeing into one cylinder it would misfire and you'd also get a shedload of smoke from the cat.

Given that the car has been laid up for a while I'm wondering if an injector has got a bit of dirt lodged in it.

I might be inclined to remove the plenum and run the fuel pump (bridge the two wider pins on the fuel pump relay). See if the intake to the offending cylinder starts smelling strongly of fuel. If you peer down the manifold runner you might even see evidence of leakage from that injector. Keep any sparks well away from the fuel vapour when you're operating the pump, obviously.

Kevin

[ScottieMV6]

Thanks Kevin (and everyone else).

I did the compression test again today and got the same result except for the 19.5 bar (this time all cylinders 15 bar). Assuming Kev is right about the weeping injector this would fit as I assume all the fuel would now have evaporated.

Put everything back together again but still misfiring and clouds of smoke.

Andy B is coming round tomorrow so we can have a look together and I will report back then. 

[GastronomicKleptomaniac]

If you spend a half hour removing plenum etc, have a look at the inlets - mine were wet with coolant on no.6 cylinder, might be another thing to eliminate or implicate HG failure

[ScottieMV6]

Andy has been round and we have decided that it can only be the headgasket. The header tank is very highly pressurised after only a couple of minutes running and the clouds of white smoke out of the back is water and not oil or fuel.

I know that the compression test would suggest otherwise but we cannot think of anything else it could be. :-/

[Del Boy]

Andy has been round and we have decided that it can only be the headgasket. The header tank is very highly pressurised after only a couple of minutes running and the clouds of white smoke out of the back is water and not oil or fuel.

I know that the compression test would suggest otherwise but we cannot think of anything else it could be. :-/

Do as Pete said mate, does sound like HG though to be honest 

[Andy H]

Sounds as though you have caught it at its earliest stage, hopefully you won't have any damage to the mating faces of the cylinder heads or block.

When you have the heads off  I would suggested having the heads crack tested. A failing head gasket would usually make the car undrivable, a minute crack caused by a casting flaw could give similar symptoms to yours.

[Kevin Wood]

Just goes to show that a compression test isn't conclusive proof. I must admit I'd forgotten about the bubbling expansion tank. Difficult to blame that on a fuel injector.

Oh, well, a bit of work ahead but hopefully we're nearer a conclusion.

Kevin

[ScottieMV6]

Yes much work ahead. I might even take some piccies of the work in progress to compliment JamesV6 excellent how to that I shall be following. 

[GastronomicKleptomaniac]

And just think, how much would you have to pay a garage to do the same? I know I'd be lost without this place...