Questionsorry for the length..i have a 98 grand am gt with a 2.4 twin cam 5spd...is that the same motor as a 16 valve quad 4 dohc?..when i start my car it idles rough and very little black smoke comes out of one tail pipe and none out of the other...when i kick it down and shift gears its like a miss..what do you think?
AnswerHi
The engine depends on year and VIN identifcation.
The black smoke is rich condition.
So a miss could indeed cause a rich condition.
Rich = Too much fuel OR not enough air.
So we can check air filter. Fuel pressure for TOO MUCH pressure.
A faulty Fuel pressure regulator can EASILY cause this condition.
Plugs, plug boots, coils.
Air flow meter faulty reading. IAT sensor &/or Coolant temp sensor reading default (-30*F).
I would think from what you stated, check the fuel pressure regulator for ANY signs of gas in the Vacuum line.
If there is ANY signs of gas, replace regulator.
Other would be a miss, plugs, boots, coils.
I hope this helps.
Good Luck
Follow post back if more help is needed.
Pawl
