Mechanics

SMOKE FROM EXHAUST

1995 Saturn SC2 • 4 cylinder FWD Manual •

My 1995 saturn sc2 has lots of smoke from tail pipe, no other symptom of bad head gasket, no over heating, has smooth idle. No oil in antifreeze no antifreeze in oil. No bubbling in antifreeze. Nothing leaking from car
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Cutter1041
November 22, 2010.




What color is the smoke? If it's white then it is antifreeze, if black, it's too much fuel(rich) if it's blue, the engine needs rings or pistons.

Merlin2021
Nov 22, 2010.
What color is the smoke. And do you have to add oil frequently (bluish/grey or dark smoke)? Also, if you have a blown head gasket (white or light colored smoke), you might not overheat right away, or get coolant in the oil.

But if it is a blown head gasket, you will eventually start overheating to the point you won't be able to drive over 50-60 without quickly overheating.

Ernest Clark
Nov 22, 2010.
Bluish white. And I drove the car forike 45 mins it dont overheat or idle rough I klnow these rmsymptoms of bad head gasket. But it only has the smoke problem. Car runs great besided that

Tiny
Cutter1041
Nov 22, 2010.
There's only three possible sources of smoke coming from a tail pipe. The most common is oil burning. That usually shows up as a bluish or darker smoke. Coolant always is white with a sweet odor. The third and most rare, is transmission fluid. And that's always mixed in with coolant.

The reason it's rare: most cars have transmission cooler lines running to the radiator. Sometimes the radiator will develop an internal crack that allows tranny fluid to mix with the coolant. Then if there's also a blow head/intake gasket, both fluids will burn out the tail pipe.

Tranny fluid will always burn white as well, but much thicker.

As for your problem, when you drove your car, did you get on the highway with speeds in excess of 50-60? The reason I'm telling you the car may not necessarily overheat is this: I recently had an Olds Aurora with a 3.5 V6 and a blown head gasket. There's no question I knew what the problem was, but I couldn't fix it right away.

Knowing what I know, I stayed off the highway, kept my sustained speed under 50 and made sure the fluid was always topped off and bled of air.

I could drive around for hours without overheating.

So back to your issue. Pull the resevoir cap, and while someone revs your motor up and down past 1500 rpms, look at the coolant and any signs of large bubbles. If there's any, you have a blown head gasket.

Next dip your finger in the tail pipe and smell it. If it's sweet, blown head gasket. If it's oily, you're burning oil.

If you eliminate the coolant as a possible source, do a compression check on each cylinder. This'll tell you if it's oil and where it's coming from.

Keep in mind, after so many miles, all motors wear internally and begin to smoke from the tail pipe.
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Ernest Clark
Nov 22, 2010.
You could also do a block test its more accurate than a finger.

Merlin2021
Nov 23, 2010.
The smoke smells like oil, so im not sure if its ahead gasket.

Tiny
Cutter1041
Nov 23, 2010.
Check compression

Merlin2021
Nov 23, 2010.

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