Hi Guys, My Zed has a smoking issue, which i'd rather it quit. After about 5-8 minutes of idling, a grey smoke starts to appear from both exhaust pipes. Its not pure blue, nor white - thinking oil or water problem, but rather a grey misty color. It doesn't smell like oil, not like you'd smell from behind a car which needs new rings. The car always runs normal operating temperatures, and hasn?t used a drop of oil or water. After noticing this issue and thinking of anything I?d done to it lately, I did add some Nulon lifter silencer to the last two oil changes. It doesn't happen while driving, infact, if you were to leave the car to idle, but crack the throttle open ever so slightly, so the throttle body butterfly is not completely closed, it wont start to smoke at all. It doesn't happen on boost, and it emerges from both tail pipes at the same time. The only time I notice it on the road is when say stuck at a intersection, or traffic. It takes less time to develop when the car has just been started. So cold start, then next intersection, it will develop the smoke, a bleep of the throttle clears it then its fine, you would have to leave to idle for 8 minutes for it to occur again. The exhaust system is aftermarket, straight through from each bank, no cross over. As it appears to happen only at closed throttle, the gas/oil/mixture must get picked up via vacuum. So I started to think PCV's. They have never been changed on this car. Or, could it be the early sings of valve stem seals? The only time the two banks cross over is via the plenum balance pipe during intake.. after combustion, each banks exhaust gas has it own pipe to travel. My question, when zed turbo seals fail, do they fail at the same time? Makes sense to me they have both done the same amount of work? The car is un modified aside from exhaust pipes, running in safety boost mode, that being its only diagnostic fault code. Any ideas, advice, areas to address I would really like to hear. Cheers. Clint
answerz The # 1...rule with anything automotive - start with and eliminate the simplest fixes first. From your description it does "sound" like excess fuel (but as everyone's perception of color can be different it may well be oil/water...) So for now, my advice is don't fret over turbo seals/leaky valves, worn piston rings for now and eliminate the more common/easy-to-fix causes such as PCV's stuck partially open, error codes 13 (CTS) or 34 (Det sensor) in ECU which put you in safety map (rich mixture), worn spark plugs not igniting mixture enough so excess gets blown out exhaust and faulty 02's which usually die in the "everything's fine-no need to lean my bank out, Mr ECU" state.
If it was valve stem seals, I believe it would smoke immediately after the car was started. Maybe change to a heavier weight oil and see if that fixes the issue.
Vid of Smokey Zed Actually taking a closer look at the exhaust system, there might be a cross over, or balance pipe just after the last two resonators, so i'll have to take a closer look at that. In any case, here is a vid of the smoke in action Vid of my smokey zed.
Take a deep sniff, excess fuel is the easiest to detect... vid quality prevents accurate color analysis...
Thanks Guys Thanks guys A new set of spark plugs is certainly a good shot, the pcv's should have been replaced anyway so they are on my list, and one O2's from datascan's results is not as active as the other, at least lazy or maybe its heater element has burnt out. I think i'll by-pass the knock at this point to cure the 34 code, if it is anything much over the above mentioned i'm probably going to be taking that plenum off anyway so I?ll tackle a replacement knock sensor then. All worth while for a tune up anyway, so I?ll tackle them first. Cheers for your advice. Clint
If you have code 34, then the smoke is highly likely to be unburnt fuel. Try a 1 Meg Ohm resistor betwwen the det sensor female connectors (see tech section) then clear the error code. That alone might be enough to eliminate/reduce the smoke
Resistor Question I got this resistor a little while back, but didn't have the actual specification on hand so guessed and got two packs. One reads RES 0.5W MTL 1M0 1% mini the other RES 1W CARB 1K5 5% is either of these correct? AHH found this from a search: In the tech section the resistor requirment is a 1 meg ohm resistor or 1000k ohm. When I went to jaycar to buy the resistor needed I found the resistors come in different wattages, 1/4 , 1/2, 1 and 5. I purchased all of them to try each one out. At Wakefield on Sunday with some help from Wizard, Ports, JT, Tokyo Geoff and Aus 300, we managed to get the 1 watt 1000k ohm resistor to work with the ecu and has eliminated the fault code. cheers
