87 Firebird running too rich?

[Vince]

My son has a 1987 Pontiac Firebird with a 2.8 V6. It leaves black marks on the driveway from the exhaust and is using allot of gas. We have replaced the fuel filter, air filter, fuel pump but it still runs very rich. Any ideas?

 

[cknarf]

I don't know much about third gens, but have you tried messin' with the carb?

 

[Zimgxp]

Oxygen sensor?