Ok here is my predicament My zed has been blowing smoke for some time but seems to have gotten worse recently. It seems to be smoking when im taking my foot of the accelerator. Never when boosting. It seems to get worse if im pushing it harder for some time. The smoke is white/gray and has a oil smell to it...not the burnt oil smell you get from someone with a blown head gasket or worn oil rings. sometimes its a little puff when i back off other times its a huge cloud and can be seen out the revision mirror I would think if it was turbo's it would smoke when on boost. If it was worn valve guides the colour would be different and it would smell like burnt oil?? If it was worn piston rings i would think it would smoke on boost and i would be experiencing power loss. Defiantly not lacking in power!! PCV and all vacuum lines have been replaced. Done 4000ks and hasnt used a drop of oil. coolant may have dropped less than 1 cup so i don't thing it would be a head gasket. I am running tune agent dump pipes and a trust exhaust system minus cats If anyone has any ideas please post them up. Cheers Brendan
Do you have a balance pipe, set up in the 'right' location? Do a quick search on the forums. Depending on how its smoking, ie right side only, this could be your problem. MoulaZX
What you describe is "classic" Oil Seal failure in your turbo's(the oil leaks passed the seals when the boost drops in pressure). Check the insides of your intake pipes for signs of an oily build-up or residue. Time for a turbo rebuild I'm afraid.
Second that 'I would think if it was turbo's it would smoke when on boost" Its the other way round, classic oil seal failure is right!
Guess it looks like i'll be upgrading the turbos. In the mean time if i tried thicker oil do you think it could reduce the amount of smoke?
Thicker oil will give higher pressure, the higher pressure will make more oil leak past the seals. The news is all good - apart from all the time and money required..... At least you have the chance to improve while you are in there
Question. Do you have atmospheric BOV's? On a rich tune or on knock maps with BOVs, when you jump off boost it's floods unburnt fuel into the exhaust and you end up with a big cloud of grey smoke that last momentarily. Not disagreeing with the turbo seal idea, but it very well could be something that doesn't require an engine pull. Also the "turbo seal" cry from every one if you mention "oil" and "smoke" in the one paragraph is my pet hate. Turbo exhaust seals - blue/white smoke below 1500rpm Turbo intake seals - blue/white smoke after boost, but not often in a puff like you describe, more of a steady smoke out of the exhaust. Unburnt fuel - dark grey, often when on boost with a factory tune or when you release the accelerator from full boost.
ERROR Thicker oil MAY stop the smoking as a temp fix as it wont leak as easy. Mine was smoking like a bitch on idle with OEM grade oil. Changed to 15w60 and now only smokes on WOT and not as much at all.
Smoking at idle could be a different issue. Mine doesn't do it all the time its always after hard boost when i back off and when it does its only just visible. Might throw on some cats for the time being and see what happens.
Im running atmospheric HKS SSQ BOV's but have removed the AFM and am running the HKS VPC and FCON. I guess i could unplug the BOV's and see if it makes any difference. You would think that running of intake pressure it would pick up the pressure change and adjust A/F ratio.
No because the air pressure/temperature/etc has already been measured and then when you back off boost, the pressure drops from the runners immediately, and your injectors still squirt momentarily as if there was a hell of a lot more air going in there.
I dont have an AFM it runs of manifold pressure so it should pick it up the change in pressure. More info on HKS VPC
Yes, I did read your post and I know the HKS unit very well, don't like them, but it's off-topic. Point still remains, even reading manifold pressure, your still going to have micro-second delay while some injectors are still firing based on say 16psi of boost, then a sudden drop to 22psi of vacuum, your going to have an extremely rich burn. All turbo cars do it with atmospheric bovs, it depends on your tune and your cats as to how much you destroy the environment.
Thicker oil will stop/reduce smoking if the engine is tired as oil pressure doesn't effect the oil scraper rings leaking on your pistons. Higher oil pressure WILL increase leakage past labyrinth seals such as those used in turbos. Ask yourself why people sell kits including orifices installed in oil lines for ball bearing type turbos - see where I'm going with this? (please don't go giving me a lecture about ball bearing turbos requiring less pressure etc as that will just show you have missed the point)
