z20let help, white smoke at idle when hot head tested 3 times shows ok

[vxlgsi]

any ideas what the problem might be?

[Ardenblueroy]

Could be a number of things....seals on the turbo could be shot. Valve stem oil seals...but that would only give smoke on start up...head gasket failure could still happen..even if a sniff test shows ok.

I'd check the cam cover breather pipe...they can clog up over time, monitor oil and water levels for any loss.
If the car has sat for a long period there could be a build up of moisture in the exhaust??

Check the simple stuff first...then start to look at the head and turbo ect.

[vxlgsi]

surely turbo seals and valve stem seals would be blue smoke.

I heard these heads can crack, where do they crack?

[vxlgsi]

it also runs abit rough when it smokes on idle

[vectra640]

Steam is sometimes confused as white smoke, in winter time steam when at idle is common as cold air hitting the hot exhaust and causing moisture, put your hand in the white smoke and see if it's wet when you take it away, not too close to the exhaust though

[vxlgsi]

yeah i know, its not steam fella.

[vectra640]

maybe water is getting into the cylinders at idle causing it to smoke, possible HG or something cracked and letting a dribble of water in at idle, does it smoke when you take your foot of the throttle pedal, PCV possibly

[Ardenblueroy]

The most common problems with the Z20LET as far as I'm aware are..seals on the turbo, poor earth connection, coil packs are made of chocolate, front and rear bcs are also made by cadburys there was a problem with the coolant/expansion tank..ect ect.

White smoke could be one or a mixture of things..antifreeze burning off (head gasket failure) oil mixing with coolant...also head gasket failure, valve stem oil seals will smoke on start up and run rough.

I'd give the motor a service, oil/filter, fuel filter and tank drain, coolant change, flush the intercooler, replace the plugs ect. Take it for a good old blast to clear her lungs...then check the fluid levels and see if there's any fluid loss.

I'm gonna assume the Z20LET is in a Corsa? Has the car been sitting for a long period of time?

If so then it could be condensation in the exhaust, crap fuel in the system, coke-ed up plugs, poor coolant...??

[vxlgsi]

yeah water in the cyclinder would atleast explain why it runs rough, but you would expect the sniffer to pick that up!

[Ardenblueroy]

yeah water in the cyclinder would atleast explain why it runs rough, but you would expect the sniffer to pick that up!

I had a MG ZR a few years back....head gaskets went on 85% of the cars made (crap K series engines)...had a sniff test done on mine...was fine...had the head removed and it needed to be skimmed and a new MLS gasket fitted.

Has the engine not been running for a while...is the Corsa a project?

[vxlgsi]

no its a zaffy gsi in daily use.

My corsa b has a clet in it, still starts on the button with no smoke no tapping after being parked for 4+ years though. I really should resurect it lol

[Ardenblueroy]

Just do the above and see what happens before spending big money.

[redtopnutta]

ive got the same problem with a sri turbo. defo not oil! turbos a good vxr item, think im gona rip the head of and give it a overhaull as its a easy enough job.

[redtopnutta]

did you sort it mate?

[vxlgsi]

fuel in the oil, just needed an oil change

[redtopnutta]

that simple? how that happen? turning engine over without coilpack connected flooding engine?

[rudeboycorsa]

sounds like the rings aint bedded in fully an over time you get petrol with the oil

[Gsilee91]

What turbo are you running on it ?? And has the car sat for any period of time

[vxlgsi]

turned out to be the common cracked head

[redtopnutta]

z20lets suffer cracked heads? mines been sitting for about a year, i cant get rid of the burning water smell from exhaust with the white smoke. but the car isnt losing water? do you know where it was cracked

[vxlgsi]

Seems to be common on just standard engines as well, cracked in the combustion chamber between valves and spark plug hole.