Starup/Performance Problem

[steddy]

Been a little while since I've been on, but I'm wondering if anyone has had this issue. I have a '96 Firebird with a 4L60E trans. Rebuilt about 2 years ago and went with a '97 motor and PCM. I bored it .030" over and put a Comp Cams blower cam into it, with 22# injectors. This year, I have been having a rough start issue and it's going through O2 sensors every 3-4 days. When I put it in gear, the rough idle goes away just after startup. It's wanting to die at lights (volts drop and car feels like it's "loading up"). Takes right off when the light goes green, but hesitates and bucks when entering the freeway. When I park, it surges. I scanned it yesterday for the SES code and it mentioned about the O2 voltage being low and something about the air control. Would the IAC cause a problem like this? Has anyone been here before?

[ssms5411]

Re: Starup/Performance Problem

IAC can mess things up , have you checked for vac. leaks ?

[steddy]

Re: Starup/Performance Problem

Sure have. I strongly considering the IAC myself. I'm also considering movine the O2s a little more down stream, considering they are burning up quick. I think I'll price an IAC and possibly change that out while I'm at it. After all, it is the OEM part. I've found, also, if I feather the throttle coming up to lights (and this is VERY slight) it doesn't want to die, which screams IAC to me.

On the scanner, it thinks it's going lean and richening up some, which is alright for the most part, but I'm hoping with a little moving, the O2s won't get quite as hot with the ceramic headers and bigger bore/compression.

[FirebirdGT]

Re: Starup/Performance Problem

Take the IAC out and clean it with TB cleaner first. Fixed a similar issue I had. Now it's normal annual maintenance.
.

[ssms5411]

Re: Starup/Performance Problem

Take the IAC out and clean it with TB cleaner first. Fixed a similar issue I had. Now it's normal annual maintenance
.

Thats true some cleaner and you might be fine with the IAC. I haven't cleaned mine in awhile so I'm sure I'm do.

[steddy]

Re: Starup/Performance Problem

Even better idea! I'll do that first thing in the morning. Wow, I can do this and not break the bank again. Thanks folks. Probably is an issue. I may just clean the MAF while I'm at it. All right there. Thanks again!