Ever since I have owned the car I notice that when Im sitting at a light the car tends to idle rough intermittently. Its like clock work. It will idle what seems to be smooth then hit a rough patch, idle smooth then hit a rough patch. Meanwhile the rpms dont change at all. Is this a characteristic of LS1s? Its not extremely rough, but enough for me to recognize it. Other then that the car runs great.

 

Im actually wondering what the symptoms of a bent pushrod are and if this could be linked to that potential problem. Im paranoid right now and hoping thats not the case

 

I have the same thing and was wondering the same thing. I am about to do a cam swap and I guess I will see if any are bent then.

 

Are you the original owner of the car? If so how high have you revved it. Im pretty sure the rev limiter on my car is at stock setting. Most posts state you will not bend the pushrods my reaching for the rev limiter. Even so Im concerned.

 

Any thoughts? Is anyone else experience somewhat rough idle? Is this normal?

 

Yes, my idle is rough most of the time and it sits at 500rpm in drive. I notice that sometimes it is smoother than others. I have no idea why, but it bugs me. I've been thinking I should change the fuel filter, but I doubt that'll help. My car is mostly stock w/39,000 miles and the plugs and wires have not been changed.

 

Sounds like the Idle Air Control Valve to me...

 

Where is this located at on the TB, and what is the best way to clean it?

 

Please give me explicit directions on how to clean the Idle Air Control Valve. I am a newbie when it comes to the TB and I dont want to eff anything up.

 

bent pushrods normal end up with a ticking sound.

Remove lid, MAF, and Maf to TB hose.
Remove the 3 screws holding the TB on.
Remove the 3 hoses attached to TB. I use the TB screws to plug the coolant hoses so they don't leak.
Take the TB off.
Put a clean rag in the intake to keep dirt out.

There are only two items on the TB, the TPS and IAC. Both come off with a torx.

I doubt the TB needs any service. I'd look at the plugs and maybe wires.

At 500 rpms, A4 tend to occassionaly idle poorly.

 

The car has 34,000 miles on it. I have read many posts where people had the same problems. I guess there IAC was full of carbon................Just out of curiosity what does TPS stand for

 

Throttle position Sensor. At 34000 you might want to change your plugs. They will last ALOT longer than that but performance will take a hit.

HMMM my car idles pretty rough too wonder what my problem is

 

How old are your plugs?
Have you done all basic maintenance?

A switch to Iridium plugs will clean up your idle a bit. Using colder plugs than stock will make your idle rough.

 

I wish that was why my car idles rough

 

Cam only takes an afternoon to install, easy to do!

 

Yeah, my 2000 Formula A4 idles very rough too, so what is the verdict? It only has 34k miles on it.

 

All of us who've complained about this on this thread so far have 2000's ... coincidence?

 

For what it is worth....

I have a 01' and 32400 miles and the idle has started to get a little rough at 600 rpm.

Plugs???

 

I thought the plugs went to 100,000 miles. I havent cleaned the TB yet, but I think Im going to try that

 

Also what would kind of solution would you use to clean the TB?