Hello, im noticing my car is idleing rough when ive driving it for 30min or more ... when i first start it up and cruise for the first 15 or so min it runs good and on the open road... but when i put it in park or i pull up to a stoplight it idles rough... i can see the rpm gauge jumping and the car feels like it wants to die but never has yet... just feels like its getting worse... general things ... 1992 firebird 3.1 ... new plugs, wires, o-ring seal... 100,761 miles... and run 93 octane, and already ran fuel injector cleaner... not very mechanically inclined but willing to learn.. thanks in advance for any help

 

also wondering if headers would be worth putting on.. the pacesetter 2.8 ones... thanks

 

It could be a few things, but i think i would check the idle air control valve first.

Is the SES light on?

Another thing to check would be the EGR.

Also, check for vaccum leaks.

 

No engine light... alright ill check those things ... thanks

 

i cleaned the acv.. and unplugged the battery...nothing... no engine light but however oce the engine warmed up thhe idleing rough continued, and when the rpms jump the power dims aswell, temp of the engine is 160-170. i aslo bought a new fuel filter and a temp sensor that goes to the block... putting them in the morning as well as cleaning the egr... it might also b backfiring a little, not sure.... any other ideas? i was told it could b a bad cat converter 2? could that cause this? thanks

 

icv*

 

I dont think it would be the cats, but i wouldnt rule it out.

At this point i would say go ahead and put those parts you got on and see what it does, and remember to check for vaccum leaks.

Let us know how it goes, good luck

 

OK, so ive put in a new egr valve, fuel filter, o2 sensor (one in exhaust), new temp sensor... cleaned the idle control valve... unplugged the battery... checked for engine codes... vacume lines...all to no avail... it seems to b missing causing the bad idle? it only does this when ive drove it for 20min or more and only when im ideling or in park... car never gets over 160-170 degrees, all fluids look good and not loosing any, anyone have any other ideas? (reminder car has new plugs, wires, oring, air filter) thanks again guys

 

Have you checked TPS?

When its cold, where does it idle at in drive?

Whats it idle at when warm in drive?

 

ok so i went out and started it... idles at 1300 when cold... after 15 min it'll go dow to 900-700 range (tach bounces.. ) but then you can here the computer telling it to give more gas and then it will straighten out for maybe 20 secs 1000rpm, then its back down to rough idleing and repeat, is this a symptom of bad fuel injector?