hello again folks,

 

Well I still haven't got to the bottom of my smoking exhaust problem. The car doesn't smoke when cold. It only seems to smoke when left idling for a while when fully warmed up and then not always from one exhaust. Sometimes both exhausts smoke, sometimes its only one.

 

The car has done 78500 miles so its probably the turbos. The smoke is mainly white but there is a slight smell of burning oil as well. I'm not too upset as thew turbos are covered under a warrenty but nly up to value of £1000. Does anyone out there have any idea of the cost of reconditioning the turbos at a nissan dealership?

 

The only other cause for the smoke that I can think of is a problem with the cylinder head gasket or the the head itself as mine is one of the very early cars. I 'll check the engine number and see.

 

Can anyone think of any other reason for the exhaust smoke? As I say it onlyn happens after you take the car for a run and then let it idel for a while. Its probably worth mentioning that thaqt car has had the cats removed when a full s/s exhaust was fitted earlier this year. The extra presssure may well have contributed to turbo seal failure if indeed that is the problem.

 

Cheers.

 

Martin.

Turbo failure will cause oil to leak and the smoke would be blue/black and not white.

 

White smoke is usually water.

 

I would guess that the head gasket is going and leaking.

 

Also saying that, I have heard from sources that decatting will cause the exhaust to smoke as the engine is over fueling.

Thanks SRRAE,

 

I've had a good look at the gauges and I reckon:

 

The oil pressure is fine.

The oil level is fine.

The boost pressure is fine both at full boost and when the throttle is closed the needle swings back to almost -7 mmHg so it looks like there aren't any problems with air in the system.

 

The smoke definetley looks white rather than blue / black so maybe the turbos are fine after all. Its wierd that the exhaust only smokes after the car is fully warmed up and even then only afetr it has been for a run. If I start the car from cold and just let in warm up slowly at idel the exhaust doesn't smoke

 

Probably best to get a compression test done and hopefully that would show up any problems with the head or the head gasket.

 

Thanks again for your help.

 

All the best.

 

Martin.

Contrary to popular belief, oil smoke CAN be white! It only turns blue if you burn it - pass it through a hot exhaust and you just get white smoke. Possibilities are:

 

Turbo rear seals

Breather system problems

Head gasket failure

Valve stem seals leaking (not likely as it would do it from cold after being stood)

 

I'd go with the breather system first - about £50 to replace the hoses and PCV valves - much better to try that than fork out well over £1000 to get the engine pulled and turbos replaced....

 

HTH

 

CheerZ,

 

Andy

Cheers Andy,

 

The car still smokes so the plan of attack is to do the following.

 

1. Get a compression test done to check to see that the head gasket is O.K.

2. Replce the hoses and PCV valves (what are PCV valves by the way?)

3. Recon the turbo's (not as bad as it sounds as I have an extended warrenty which covers the turbos up to a value of £1000)

 

Will I be damaging my engine if the turbos are bruring oil and I don't do something about it ASAP?

 

Cheers.

 

Martin.

PCV valves are Positive Crankcase Ventilation valves - look about half way down the underside of each side of the intake manifold, and there's a ruber hose attached to a screw in fitting, that goes into a protruding part of the manifold - the screw in part is the PCV valve..

 

Basically it regulates the flow of air through the crankcase (there are breather pipes at the front as well) under various driving conditions, and it's designed to try and reduce oil contamination/breakdown due to combustion residue gasses as well as keep crankcase pressure down to the right level.

Just spioken to Slivia Engineering who reckons it is the turbo seals. They have quoted £950 for reconditioned turbos and £700 to fit. OUCH !!!!

 

There must be a cheaper way !!

 

Cheers.

 

Martin.

The cheaper way is to replace the PCV valves, I had exactly the same symptons as you and once replaced the smoke all but dissapeared.

 

defiently go that route first.

Well i wouldnt bother with reconned tubs TBH - Smithy used to sell a pair of hybrids for £1000 IIRC, if your going to that much trouble id fit those

 

deffo worth doing the PCV valves 1st as a few on here have had smoke problems cured/improved by doing these.

Cheers Guys,

 

I'll have a look at the car when I get home tonight. Where is the best place to get PCV valves (other than from a Nissan dealer?)

 

Cheers.

 

Martin.

Mike Feeney at MJP in Essex, or Courtesy Nissan in the states if your ordering lots of other stuff!! :D

Cheers Paul,

 

Just in case it is the turbos does anyone have any thoughts on the best place to get hold of a new pair?

 

Cheers.

 

Martin.

contact Smithy on this forum for a pair of Hybrids

Sorry to appear stupid but what are hybrid turbos and are they better than the original ones?

 

Cheers.

 

Martin.