I just installed my Pacesetters LT in my 2000 SS with catted Y-pipe and it feels rough as heck at idle and acceleration.. Why would it do this? PLEASE HELP ASAP

 

Running too rich could be a problem, but most likely your computer is just relearning the A/F curve, and after a few hours of driving will return to normal.

 

Could it be that i didnt install my O2 sims yet?

 

Please help fellas!! Also the "service engine soon" light blinks on and off when i accelerate? But then turns to just on when i slow down.. HELP!!!

 

Blinking SES light= BAD misfire. Change your plugs & wires, if it's still doing it then have it scanned.

Also, if you haven't installed your O2's yet... do it right away.

 

He said O2 sims...so that shouldn't be a problem. I would go over all the wires and plugs, just to make sure.... If not, the O2s might be going...

 

LOL yes, he did indeed mention O2 simms--- in the same sentence as "didn't install yet." Get those in ASAP, and if you SES light it still blinking it's a misfire.

 

the sims will get rid of that code in the engine. but NOT having them won't cause a blinking SES.

i'd bet you have a bad wire, plug or a BAD exhaust leak.

but remember no rear o2 sensors has NO affect on the running condition of the car

 

Instead of getting o2 sims, just get a mail order tune to delete the rear o2's and while you're at it, get the car tuned for your LT's. If you deleted AIR and EGR get those codes taken out as well. Much simpler IMO then hassling with o2 sims when dealing with LT's as they only have provisions for the front o2's in the collectors.

If this doesn't take the code away, you need to replace the front o2's as these are what send the PCM air/fuel data to make the car run right. If/when you get new o2's for the front, get some rear o2's for a 2002 Vette. Also Bosch 13111 o2's are popular as well for us LT guys. The front o2's are placed farther from the engine and don't get as hot as they did with the manifolds so you're gonna need higher watt o2's to compensate. Otherwise you'll just run rich. Trust me this is a common problem when installing LT's.

Jason

 

Ended up being a Misfire in cylinder 7.. Son of a.. Fixed it and now runs perfect.. Just need those O2 sims now..