Black-smoke out the tailpipe

[roucka]

Hello;
When I start Grand Prix GT (2001) in the morning it billow's black-smoke out the duo-tail pipe(s)...recently the oil was low and filled it , the coolant also needed capping up which has since been done...the engine itself is not emitting smoke just out the back, when you rev it up it passes- could it be that there is not enough room (re:oil) whereby it is burning?
Any input appreciated. Mancini

[GTP Dad]

If it were oil the smoke would be blue. It sounds like you have an extremely rich condition, this can be caused by a bad O2 sensor although you should be getting a SES light but not necessarily. The other thing is that the cold start circuit that automatically enriches the mixture could be putting too much fuel into the engine. One thing you can do is remove the throttle body and clean the carbon from the IAC and the back of the throttle body. This will clear the passages and should make it better. Just a couple ideas!

[jeffs_GTP_sleeper]

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