white smoke on start up
#1
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Recently completed a head and head gasket install on a 95 1.8 miata. Ran a compression test and it returned 190 across the board. The block only has 94,000 miles on it and the head was a low mileage head with new valve seals. Yesterday the car ran fine and there was no smoke on startup, but today he went to start it and there was a **** ton of white smoke. His car was doing this before the head swap and we believed the valve seals in his old head were leaking. The head gasket was replaced with an oem one. any insight into why it is smoking will be greatly appreciated.
#8
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Coolant doesn't make smoke, it makes steam. There is quite obviously a fundamental difference between the two. Be specific when discussing these things because accuracy matters.
Idle the car for 5 minutes and then is rev it up and see if it produces larger quantities of smoke. That is usually a good indicator of a valve stem seal or valve guide problem. It will produce almost no smoke at cruise if it is valve stem seals.
Are you experiencing large amounts of blow-by when you pull the oil filler cap while the car is running? That could point toward ring/cylinder issues.
Idle the car for 5 minutes and then is rev it up and see if it produces larger quantities of smoke. That is usually a good indicator of a valve stem seal or valve guide problem. It will produce almost no smoke at cruise if it is valve stem seals.
Are you experiencing large amounts of blow-by when you pull the oil filler cap while the car is running? That could point toward ring/cylinder issues.
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Could you give any more detailed info as to exactly what conditions the smoke shows itself, not just pulling away from a light, but RPM, load, engine temp, any hard runs just prior to the smoke, ect. I'm skilled at being stubborn with smoke issues. I ended up having oil ring failure after a head swap, and couldn't accept it, and went through 4 head gaskets before I gave up and rebuilt the bottom end. If I had used my head instead of blindly sticking to my one way thought process, I would have known it was the rings, since it smoked more revving without load. I also mistook the color for coolant steam, but I again should have noticed it was more oil smoke color and lingered for longer than steam would have. Smell also tricked me, not sure how that happened, maybe it was both oil and coolant.
#12
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Its not my car but from what i gather, the car did not smoke yesterday. He drove it around did a couple of brief pulls nothing insane the car ran perfect, he parked it overnight. Started it this afternoon and said the car was producing a lot of smoke at idle. I don't believe he drove it, he just let it idle and maybe reved it.
#15
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While rebuilding my crx I had an issue with constant smoke coming out of my exhaust and also continuous water dripping out. Turned out to be a bad cat.
Tell your friend to drive the car around for a while then park and let it idle. If there is still smoke you have an issue. If not then it was just water sitting in the exhaust from condensation forming after the car cooled down which is normal.
Tell your friend to drive the car around for a while then park and let it idle. If there is still smoke you have an issue. If not then it was just water sitting in the exhaust from condensation forming after the car cooled down which is normal.