HELP! SLIGHT SMOKE DURING LOW IDLE?

[BROOMRIDER1991ZR1]

After my husband following me home the other night he noticed the left tail pipe smoking slightly when I was sitting at a low idle. Please give me any feedback on why this might be occuring. Thanks for the help!

[guinnessdood]

Originally Posted by BROOMRIDER1991ZR1

After my husband following me home the other night he noticed the left tail pipe smoking slightly when I was sitting at a low idle. Please give me any feedback on why this might be occuring. Thanks for the help!

First question...What color is the smoke? If it's black...it sounds like injector issues (running rich prior to the injectors dying...which will then be a lean condition and a miss on the cylinder). If it's blue, then that's oil...could be rings or the absense of valve seals causing the smoking. If it's white...that is steam...you likely have a blown head gasket or water is getting into the combustion chamber somehow...

[tccrab]

Originally Posted by guinnessdood

First question...What color is the smoke? If it's black...it sounds like injector issues (running rich prior to the injectors dying...which will then be a lean condition and a miss on the cylinder). If it's blue, then that's oil...could be rings or the absense of valve seals causing the smoking. If it's white...that is steam...you likely have a blown head gasket or water is getting into the combustion chamber somehow...

Good advice, Uly.

Was it cool outside and the car was cold? If so, it could have been condensate coming from inside the muffler.
If you live in the North (east or west) it's probably already cool at night and you could just have been seeing normal tailpipe clouds.
Is the car running OK? Any miss or hesitation?
What color is the antifreeze (please say green)?
Having any unusual problems lately, i.e., hard starts, backfires, funny sounds?

We'll need to know a lot more before we can make any kind of educated guess.

TomC
'90ZR1 #792

[BROOMRIDER1991ZR1]

Thanks for your suggestions. It was hot out that day and I know that the smoke was not black white possibly blue will have to check on that. The antifreeze is very green and the radiator is a new racing aluminum one. The car runs cool and the temp rarely goes up at all. The car has power effects exhaust and I do sometimes get a backfire on downshift and sometimes shifting into the lower gears. The car is running smooth, and I don't notice any hesitation.

[zr1mom]

If an early year ZR-1 they don't have valve guide seals so what you are seeing might be normal.

[guinnessdood]

Originally Posted by zr1mom

If an early year ZR-1 they don't have valve guide seals so what you are seeing might be normal.

Agree 100%...my car smokes (blue) a bit as it is a 90...it smoked when I bought it with 22K miles...normal operation...as long as it isn't too much. No seals = a little blue smoke.