I have a 92 twin turbo zed that I bought second hand about 6 months ago, its had a fair few bolt on upgrades, replaced boost lines, hoses etc. and from what i can see its been very well taken care of, the compression test was great and we even did a boost leak test too and everything was looking good. its been driven every day and it hasnt skipped a beat.... until a few weeks ago I was just wiping my windscreen over before I headed out, the car had been idling for maybe 6-7 minutes (from cold) when I noticed a little bit of grey smoke coming out of the drivers side exhaust (only the drivers side). It gradually got worse and when I gave it a little rev even more started to come out. It smelt oily and was a very light grey almost white smog. this is the first time its probably idled that long as i normally let it warm up for a couple of minutes before I head to work each day. the only thing ive done since ive had the car was an oil change about 2 months back (to the same oil as the sticker that was on the windscreen) so its got me puzzled. however I did come across a thread on here from a while ago talking about the lack of a balance pipe on an aftermarket exhaust could cause a smoking issue which is very similar to this one. The exhaust is a 2.5 inch xforce with high flow cats, test pipes, dump pipes and apparent new o2's. now it will only do it when I let it idle for about 6 mins there is no other smoke at all when I drive ( even had my old man follow behind me ) do you guys think a balance pipe could be something worth looking into? or should i start looking towards valve stem seals or a possible turbo seal. I know its hard to diagnose this sort of thing over a post I just wanna know where I should begin? thanks
Try a balance pipe first, you've got nothing to lose. See this thread: http://www.aus300zx.com/forum/showthread.php?t=273457 Lack of back pressure can cause smoking issues at idle. Get a balance pipe fitted and usually fixes the issue.
If it helps to ease your mind I've had the exact same issue .No balance pipe, smokes after five or so minutes idling... and both turbos have been overhauled. Owned the car for ten years and drives fine. Only see this problem if I let it idle too long. Cheers ,Andy.
Balance pipe worked for me.... Had a new exhaust built, asked them to add a balance pipe, as previously it had gone through an common muffler. They forgot to add the balance pipe. Smoke started - car had never smoked before. Went back, asked them to fit the balance pipe - they told me it won't help. Fitted balance pipe - smoke stopped - hasn't smoked since.
Thanks guys I really appreciate the input. Looks like its time to book in to get one fitted! Fingers crossed!
It aint a "balance" pipe.... That's across the plenum or throttle bodies in the engine bay between the side of the engine... Its a H pipe or X pipe..... crossover pipe.....
If you look inside the plenum and see oil residue - you will know it's a turbo seal If you look at the spark plugs, you will know whether you will have to do a leak down test for rings/ valves etc. Doesn't take long to do either and can help eliminate cause
