My 94 V6 has just started running rich. I have a new cat on there, and it idles at 750, just shakes alot and you can smell gas when I shut it down. I just even passed NJ emissions, I'm just wondering what it could be. I have about 89,000 miles on it -- It smells bad, the exhuast is very loud, and it shakes at idle. Could this be a MAP sensor? Can anyone point me in the right direction? Thanks alot.

 

Oh, and I just replaced the CAT w/ a weld on unit from Midas. The car is an auto, and it drives fine, it just idles terribly and reeks of gas. I've always had problems w/ my gas cap as well -- it's hard to put on -- could this have anything to do with the gas smell, and if so will any 93-up f-body gas cap fit my 94?


Thanks for the help.

 

The dreaded fuel problem raises it's ugly head once again. Could be something as simple as a plug that's fouled, bad wire, or fuel pressure regulator that's not "regulating". Could also be the IAT or the MAP like you're suspecting. My suggestion is, if you have the tools...check the fuel pressure to make sure it's where it should be. Then change the plugs...and so on. You're not getting any SES or check engine lights are you? That would pretty much eliminate any sensors, but stranger things have happened. Don't think your new cat should have this effect on the performance of your car. Probably just luck it didn't act up during your emissions test.

 

I changed the plugs and wires a while back, and it was still acting up, I figured it might be something else. I replaced the cat because of this condition, and the cat I replaced had gone bad, but wasn't the cause for this condition. I'm probably going to end up replacing a ton of crap just to get at this problem -- I'm going to test all the sensors tonight, and replace anything that's shot and see if that does anything, then I'll go through wires and plugs and eventually the nightmare of fuel injectors/fprs/etc. What's the best way to test fuel pressure? Is there a fitting on the fuel rail?

Thanks for the help, hopefully I can get this straightened out.