Mechanics

MY CAR HAS WHITE SMOKE COMING OUT OF THE EXHAUST, A VERY STRONG ODOR OF RAW FUEL, LOSS OF POWER, STUTTERING AND SHAKING. ARE THESE RELATED PROBLEMS?

1997 Buick Lesabre • 89,000 miles

I have a 2 owner Buick that was well maintained. Recently it started to sputter a small amount, it is getting worse now, we have checked coils that is not the problem, we have replaced the quick connect to the fuel rail, we don't see any leaks, the oil is not dirty, the car does not over heat, We cleaned the MAF sensor. The car has a strong order of raw fuel and is blowing white smoke out of the tailpipe, and the stutter is strong enough to shake the steering wheel.
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Coriandnoah
August 29, 2012.



White smoke is due to burning coolant, typically from a leaking head gasket. Is the coolant level going down in the reservoir?

Caradiodoc
Aug 29, 2012.
We have checked that and there are no signs of a head gasket leak, all of our fluid levels are fine and not dropping. The white smoke just started a couple days ago. After all the stuttering and shaking. With the white smoke comes a strong smell of raw fuel.

Tiny
Coriandnoah
Aug 29, 2012.
A couple of days is not enough time to notice coolant loss from a head gasket leak. The other symptoms suggest a misfire due to loss of spark. When that happens, unburned fuel and air go into the exhaust where the unburned oxygen is detected as a lean condition. In response, the Engine Computer commands more fuel to all of the cylinders. No matter how much extra fuel it adds there will still be that unburned oxygen so it keeps adding more and more fuel. You can prove that with a scanner by looking at the short term fuel trim numbers. They will be very high positive and you will smell that unburned fuel at the tail pipe. There should be a lot of black smoke too. Unburned fuel causes black smoke.

Caradiodoc
Aug 29, 2012.
Ok we will look at that, but no black smoke coming out of tailpipe, just white.

Tiny
Coriandnoah
Aug 29, 2012.
You can also pull the spark plugs and compare them. Burning coolant will wash that cylinder and spark plug uncommonly clean. The plugs in the rich cylinders will be black and covered with soot.

Caradiodoc
Aug 29, 2012.
We will be able to check that tonight. My husband has been saying the same thing, he said he will be checking the spark plugs again, and for leaks in the head gasket and in the intake manifold as we heard that could be problem. The hard part is trying to determine if we have two separate problems or if this just one problem?

Tiny
Coriandnoah
Aug 29, 2012.