Ok this is actually about my 95 Cavalier, but I still think you guys can help me out. My cat and muffler went bad on my car so I bought a Catco stockreplacement Cat and a stcok replacement Pacesetter Monza cat-back exhaust. Ever since I put it on I'm having all kinds of problems. First, after the car warms up the cat glows bright red and smells horrible, why? And second, it seems like the car is hesitating a little. The car doesnt get up to speed as fast as it used to, and the old piping was 1-5/8", the new is 2-1/2". Any ideas of what is going on? I thought it was the fact that only 3 cylinders were working, but I fixed that(needed new wires, no cumbustion in that chamber). It is a little better not much. It seeme like the whole car is just slower. Excessive backpressure? I will try to reset the computer. Doubt that wil help. Also, when I pull the tube for the PCV off the car revves high, when I put it back on the car stalls. The car is also idling at 1,000 rpm's, usually its 500. I will take any ideas you canthrow at me, just please help.

 

It is glowing for one of 2 reasons.

Running lean, or it's clogged (you say oh how on a new cat), you've got me.

that would explain the hesitation if it's clogged.

 

Will resetting the computer fix the running lean problem? Seriously how can a brand new cat be clogged?

 

Try hooking up a vacuum gauge to a good manifold vacuum source. It should pull, I'd say 18 - 20 inches of vacuum warmed up at idle. If your reading is much lower than this, I'd start looking at all of the vacuum hoses, if they are cracked, brittle or very soft, replace them. Also check to make sure your throttle body is torqued properly. Just a thought, don't know if this would make it run lean, or just make it not run, but have you changed your fuel filter lately? That's all I have off the top of my head, hope it helps.

 

I know this sounds stupid but is the cat on the right way?

 

No the cat is not on the wrong way! I think I mught have leaky injectors, i can see gas coming out of the tailpipe. I'm gonna put in some used ones from a 99 Z24 Cavalier and see if that fixes it.