Since I installed SLP 1-3/4" headers (no AIR) on my car (87 Trans Am 305 TPI), it has been running very rough, sometimes rough enough to stall at idle. I've searched the boards for things to check. Checked the O2 sensor. I haven't checked the signal sent, but know the connection from sensor to ECM is good. I haven't checked the signal it puts out since the sensor wasn't bad before so shouldn't be bad now. Checked TPS setting. Perfect .54 volts. I'm headed out to put new plug wires on now. Anybody have ideas other than what I've done?

Thanks,
MikeS

 

Plug wires are a start, but what about the plugs themselves? It's possible you could have broke one or a wire is sitting on the headers.

 

I would guess the wires or plugs also. Maybe one ic cracked, or one of the wires was pulled off the socket. There really isn't anything much that can go wrong when installing headers. Well, I say that, but I have never done it on a TPI car, so I could be wrong. I would look at the plugs and wires. If its close to tune up time, buy new ones anyway, and see if it helps.

 

I'd never installed them on a TPI car before either. I got all my wires made up, but it got dark before I could put them on. As far as plugs go, I put in new ones after the header install was done, so don't expect any problems there. I had an code 13 when I pulled codes the other day (oxygen sensor circuit), but when I erased the codes it didn't come back. So, I'm really hoping these new wires help out. Once again though, the old ones worked fine before the header install, so I don't see why they wouldn't work just as well after.

At least you guys are thinking along the same lines that I had been. It feels like ignition problems. I just don't understand why I would be having any. I'll be getting up early tomorrow to put the new wires on. I'll let you know how that works out.

Thanks,
MikeS

 

firing order? 5&7 are close in firing order. Made that mistake once. I would also agree with checking for cracked plugs or burnt wire. I started my engine up 2 weeks ago (SLP 1 3/4) and burnt a wire. Just finished taking the left side apart tonight to replace wire and a gasket tomorrow.

 

88GTAinRI,

Good idea. I marked the wires as I took them off but will check everything again in the morning.

 

edit: triple post or something

 

Yeah recheck those wires, I know I crossed 2 of mine up and caused backfires thru the exhaust.

 

Well, sure enough, that did it! Runs much better now. If only I can hurry up and get some brackets on my exhaust to keep it off the speed bumps, I'll be set.