An old friend of mine stopped by last night and mentioned he had bought his son a 85 Laser to get back and forth to school. It's blowing alot of black smoke so we're getting oil into the system somewhere. Wondering what a good method is to determine if the turbo seals are shot. I know it could be valve guides, seals, rings etc also, but we'll look at the turbo first. Thanks to all who respond. G.P.
Black smoke = running way too rich.
Is the vacuum line to the map sensor in good condition?
Yes, black = gas
Pull the vacuum line off of the fuel pressure regulator and check for gas in the vacuum line. If the diaphragm in the regulator is broken, fuel will be sucked into the engine through the vacuum line.
MAP line and regulator line are the two quick things to check. After that, fuel pressure too high, leaking injector, etc.
Thanks guys. A quick check of things last night revealed the vacuum line to the FPR was broken. The O2 sensor (single wire) is not responding the way it should too. Never dropped under .350 and never above .650. Probably wasted (it's a Bosch). Maybe I better rephrase things, the smoke isn't black it's blue (now that I saw things myself...). and it's pretty heavy... I hope I haven't come upon a Frankenstein here. Any more input much appreciated. G.P.
White = oil
Pull the line off from the compressor to the throttle body and check for excessive oil.
blue = oil
white = coolant
Well, technically you are correct, but IMO most people will look at a car burning oil and say the smoke is white.Originally Posted by chilort
if it smells sweet its coolant.
OK on to an update. The above mentioned car is now in my driveway. Going to pull the head this weekend and have it checked over. Compression looked ok, 135-140 across the board, and plugs looked good. However...its throwing a code 51 (o2 too lean) and a 22. I caused the 22 I think when I checked the timing out of curiosity. I unplugged the coolant sensor and plugged it back in (per the Haynes book) and could not see a timing mark...And the fan did not come on.
I'm not familiar with the 84 turbo set-up so could somebody coach me on the timing procedure if I did it wrong? I'm going to check all the pulley/timing marks
tommorrow. I know checking this stuff probably isn't going to solve the smoking problem but hey, you never know...All input and ideas much appreciated. Thanks. G.P.
Reply With Quote
