hey guys having issues with my car it is randomly blowing white smoke it is oil burning but i cant track it down i was under the impression that it was the pvc valves but it was not that i changed them today. engine has just been pulled due to blown turbo and was rebuilt, the car mainly blows smoke when idle or at low rpm, once under boost the smoke seems to clear up and comes back when it is idleing again. engine has good compression in all cylinders and there is no sign of oil in coolers or intake, i have checked for blowback etc all seems clear its got me stuffed any one got any ideas. cheers pauly
Did you have the turbos rebuilt? Sounds like they are letting oil past the seals. Depending on your exhaust design, often an easy fix is having a H pipe fitted just behind the cats. A H pipe is just a short length of pipe which joins the two sides together. This has been very succesfull in the past with similar complaints to yours. Your exhaust guy and mechanic will both tell you it won't work, but just get it done. For the $50-100 it may cost it could very likely fix the issue. The reason it works is a bit technical and I don't claim to completely understand frequencies and wavelengths etc but basically each cylinder puts out a pulse into the exhaust, the frequency and timing of these pulses can coincide with the resonant frequency of the turbine seal. That seal is exactly like a piston ring in type and operation, using the pressure in the turbine housing to force the seal into the inner edge of the groove and the bore surface of the turbo chra. When that seal vibrates or more accuratley resonates, it can no longer stay in proper contact and allows oil past. Fitting the H pipe allows both sides of the engine to flow into a common chamber, with opposing pulses cancelling each other out you increase the resonant frequency to a higher level. At that higher level, you have more rpm, load and therefore exhaust pressure to over come the vibration of the seal. Now, if you already have a h pipe, or single exhaust, disreguard the above and have the turbos rebuilt as they are shot.
Running rich NEVER produces WHITE smoke(black sooty smoke is what you will get). Oil smoke is generally Blue/Grey and Water/Condensation will show up as WHITE(steam). a2zed has given the definitive answer to the original question.
it has a single hks dragger fitted from cats back is it possible it could be the valve stem seals ??? or even possibly some form of sensor. i no my cats seem to be preaty cactus could it also be that there not getting upto tem and causing this problem. the car itself boost perfect and runs realy well then randomly starts to rough idle then start blowing white smoke its quite embarrasing as it looks like a blown turbo seal but has no sign. cheers pauly
The answer will be easier to determine, once you have your exhaust system in perfect shape(replace your failing Cats).
seems to have been a stuck valve, i done another comp test all cylinders bar number 1 had between 140psi to 155 and no 1 had 70 psi i put oil down there with no change. i investigated further and found my injector was also not firing as it had a block in it once i got it unblocked and fireing i heard a click and what do you know now i have 150 psi again and the smoke seems to have stoped after a run. so my last question could a stuck open valve have caused all the issues. cheers pauly
Given that the Z32 has an "interference" engine(an engine in which the pistons will make contact with the valves if said valve does not return to the closed position)it seems highly unlikely that you could avoid a damaged piston/bent valve stem under such a scenario. This might be a good time to find Religion. P.S. I'm glad your engine seems to be working correctly again.:zlove:
i dont know why the valve wasnt quite sealing but there is no damage to the piston or cylinder by the looks of it i have a micro inspection cam which i put in the cylinder its got me stuffed. the engine is a little ticky now but idles and runs heaps smoother.
The engine seems a little ticky? Is it still just at idle that it ticks? Could it be oil viscosity? I highly doubt it, I'm just throwing it out there. Also is it possible engine oil level is too high?
Try checking the injectors . I had a pulsar once that would not boost properly and didnt idle the best either . Found out I had a bent injector pin . Swapped for another used injector and bingo all was well . Its amazing how an injector can cause alot of issues . Good luck mate .
