1989 pontiac sunbird SE help please

[plipke]

my sunbird is blowing black smoke from the exhaust i'v changed O2 sensor plugs and air filter yet it still does it when the gas is pressed too much gas is being dumped into the manifold what could be causing this? please help

[GTP Dad]

Welcome to AF!!

It sounds like you have a problem with either the injectors sticking open or the ECM is telling them to stay on too long. Either way you need to do some diagnostics in order to find out what is going on.

[anomaly_va_1976]

Check your vacuum lines at the MAP sensor and the throttle body, one or two of the vacuum lines at the throttle body will cause a 3.1 to run extremely rich. Unfortunately... the MAP sensor line has been known to break off under the top plenum where you can't see it..... MAP sensor is located at the firewall side of the intake manifold upper plenum.

On another note, my Beretta was loading up with fuel and idling like it had a full race camshaft and blowing some black smoke, turned out to be a bad ECM....