Do these car allways not idle smooth? Probally just got to live with it. Its just allittle stumble here and there. It seems to have gotten worse after I put in a new EGR.

Who's car seem to have a smooth idle. I spoke to many friends and they said majority of the third gen are like that.

 

well my car idles pretty smoothly most of the time, a little stumble isnt a big deal but i dunno if i would consider it perfectly normal, things can always be adjusted

 

My 88 GTA seems a little rough at idle. Nothing serious, but I can feel the engine running. I have the 350 in my car. I've asked this question before. My car idles around 500 rpm's. That's just enough to keep it running. I've noticed that all are like this. What I figure, is that with the 350, if the engine idled at 1000 RPM's, it would give you whiplash every time you let your foot off the brake in an intersection. Hold your left foot on the brake, and with your right foot, bring your RPM's up to 1000 and let your brake off. See how fast it takes off and you'll see what I mean. So, I wouldn't worry about it. It's perfectly normal. Matt

 

Never got my stock L98 to idle smooth, I cleaned, checked, changed pretty much everything that has to do with the TPI and still a rough idle. My Olds 307 carb idled smooth and family's 96 Caprice with a L99 idles smooth. Im cammin now so all my attemps would be futile.

 

The little things will get you.

I fought a intermittent rough idle with my TPI 350.....this was after cleaning the IAC, throttle body, resealing intake ( coolant leak ), all new gaskets, new EGR and hard vacuum lines etc.......

After new spark plug wires ( Taylor 8mm ) and a DUI cap, coil and rotor and module ( replaced newer stock replacements ) idle smoothed out a good bit.....I also replaced every vacuum line in the engine compartment, and that helped as well.......

It's glass smooth now, except every now and again, ONLY when really cold outside, it will idle a bit lower than normal, and feels a tad rough, but as soon as it warms up to operating temp it's great.


HTH

 

My car idles fairly smooth. Do all the regular tuneup stuff, it helps. Check your injectors lately? That's another thing that is problematic. There was a thread about late model third gens, and injectors that go on the fritz. One bad injector is all it takes.

When you say rough, how rough are you talking about? unstable within 100 rpm or more? I've had 2 problems that affected my idle. Bad ECM and faulty injectors. The ECM pushed my idle speed up and down, even up to 1500 in neutral, then it would drop, and act all nuts. The faulty injectors were a pulsating issue, but regular in pattern. Neither showed any warning codes.