1989 Chevrolet Celebrity - running rich?

[n0c7]

It all began about a month ago. The car was running like shit so it was time for a tune up. We replaced the fuel filter, plugs, injector, EGR valve, PCV valve, air filter, etc. I missed the o-ring seal on the new injector and flooded the engine. After dumping the oil and cleaning out the plugs and installing the o-ring seal on the injector, the car ran fine.... for a week. Then we had misfire on cylinders 1 & 4. Replaced the coil for 1&4, ignition module, and plug wires. Car ran fine for another week.... then the check engine decided to come on. The car seemed to be running rich - black carbon smoke blowing out of the exhaust, stalling when coming to a stop, stench of fuel, etc. We replaced the O2 sensor(the old one was most likely the factory one and was long over due). It was full of carbon. The car ran fine for a day, then the light started coming on. I disconnected and removed the O2 sensor and reved it up about 6-8 times to blow some of the carbon out of the manifold, and boy did ALOT come out. I wiped off the new O2 sensor and reinstalled it. The car has been running better for a day now, but if it starts running rich again, whats next and how can I clean out some of this excess carbon? We also just filled up yesterday and put in fuel injector cleaner.

[prong2002]

Do you get any error messages from the computer. There are two connectors on the computer reader port that can be shorted out with the ignition turned on. You will get access to a few codes. I wonder if you're getting the same problem that I was getting with my 1988 chevy silverado. Are you getting Black Exhaust?

[n0c7]

Originally Posted by prong2002

Do you get any error messages from the computer. There are two connectors on the computer reader port that can be shorted out with the ignition turned on. You will get access to a few codes. I wonder if you're getting the same problem that I was getting with my 1988 chevy silverado. Are you getting Black Exhaust?

Code pulled was "Rich exhaust" and yes black smoke when the check engine light kicks in.