Corvette Forum : DigitalCorvettes.com Corvette Forums banner

1 - 6 of 6 Posts

·
Registered
Joined
·
31 Posts
Discussion Starter #1
Hello,

I noticed my 98 vert idling a little rough this week.
I noticed it after I filled up with Shell Premium last week.

I added some Lucas fuel treatment, but it still does it.
I have a little less than half a tank of that gas left.

It doesn't do it all the time... I will be driving and come to a stop sign or light and it feels like it might die (it never has) if I don't give it a little gas. Or sometimes it is normal.

I am getting no errors or messages on the DIC

Can bad gas cause this?

Thanks
Tony
 

·
Premium Member
Joined
·
17,444 Posts
Hello,

I noticed my 98 vert idling a little rough this week.
I noticed it after I filled up with Shell Premium last week.

I added some Lucas fuel treatment, but it still does it.
I have a little less than half a tank of that gas left.

It doesn't do it all the time... I will be driving and come to a stop sign or light and it feels like it might die (it never has) if I don't give it a little gas. Or sometimes it is normal.

I am getting no errors or messages on the DIC

Can bad gas cause this?

Thanks
Tony
I think I would give it another tank before I started taking it apart. Might look and make sure every thing is tight on your air intake and filter. a loose air bridge clamp will some times cause that.
 

·
Registered
Joined
·
6 Posts
Rough Idle

I have had the same problem with our 2001 Vert. It has been modded with the Vortex ram air intake and smoothe air coupler bridge.

The condition was that it would "seek idle" between 500 and 800 RPMs when the AC was turned on and never really stabilized.

First, I found a dirty air filter and cleaned it. This did not cure the problem. Next, the idle re-learn procedure was done, to no avail.

Next, I removed the air coupler and found that it was deterioating slightly on the inside and depositing rubber dust into the throttle body. This mod was disguarded and thrown in the trash, as I never noticed a difference with it anyway.

The throttle body had evidence of fuel/contamination deposits on its throat, as well as the area leading into the TAC (Throttle actuator Control) on the driver's side of the throttle body.

The throttle body was then cleaned thoroughly with carberator cleaner. I again performed the Idle re-learn procedure.

This completely resored the idle to 800 RPMs with no fluctuations. I think that this was a cummulative problem that led up to deposits within the TAC, that caused it to respond slowly to changes directed by the PCM.

No codes were ever present prior to the diagnosis, troubleshooting or repair, other than the ones set during pulling fuses for the idle relearn procedure.

Hope that this may be of assistance.

Z450HP @ Classic Glass Corvette Club, Marietta GA
 

·
Registered
Joined
·
10,035 Posts
i had symptoms like that chaged the cat converter all is good now

also injectors messing up can send symptoms i changed two on that occation test for them by grounding out ech plug wire if it doesent affect the idle its one of them gone bad

cosmo
 
1 - 6 of 6 Posts
Top