hey club~!... i have a 1989 trans am.. TPI , i'ev put on a flowmaster and a high flow catylitic converter , i'ev also put in a new oxygen sensor., replaced all spark plugs and wires. checked timing... changed oil ... but the car still runs rich... really RICH. before and even after all this i'ev done ... if anyone can help me figure out this problem .. it runs so rich i get about 11 miles a gallon... it's so rich i can smell the gas comming out of the exhaust when when i'm in the driver seat idleing at a stop light.
the exhaust has no leaks.

 

is your fuel pressure regulator plugged in? thats all i can think off.. unless your injectors are bad, or one is bad, it may be dumping fuel into the engine. to check the injectors, use a multimeter and check the resistance acros the two leads, withthe injector unplugged... should read aroun 16Volts

 

I don't know how it even runs if it's that rich. I can pop off 15-18mpg and my car runs so rich that it keeps fouling plugs.

 

Check your regulator first, I have seen regulators rupture and cause the same problems. Pull the vacume line off the regulator and shake it to see if any fuel spills out. If there is not any fuel in the line than next check the pressure, should be in the neighborhood of 43psi plus or minus a couple of pounds. Also check to make sure the vacume source to the regulator is working at an idle and not plugged up. Check this all out and see what you get, there is still other things to check but this should provide for a start.

 

I'm with Jim85Iroc .... I get 19-20mpg easy and I'm running 24# injectors with a 22# constant in the chip. Running so rich I have to change the plugs with every oil change because they get fouled out so quickly.

Your fuel pressure regulator diaphragm has probably got a hole in it.

 

It definitely wouldn't hurt to check the TPS sensor as well. If it's reading too high (incorrectly, unplugged, etc.) it'll dump in lotsa fuel thinking it's at WOT.

 

26lbs on a 19lb chip for me.

 

I'm running 24# on a 22# chip, and I'm running lean according to the BLMs. Explain that one.

 

Wheres that?