Motor idle.

[Leonard 3.8L]

Well, I've been noticing lately that my motor has a weird idle to it. It idles at around 1,000 RPM, then it goes below 1rpm then shoots back up and all over again. It sounds like it wants to stall out but it does not. I was just wondering if any of you have ever had this kind of thing before; and what did you do to fix this. Throttle position sensor is what I am leaning towards. I've changed my oxygen sensors earlier this week so it's definitely not that. Any ideas?

[cam98aro]

Re: Motor idle.

try cleaning the MAF, EGR and check for any vacuum leaks

[jimmysprinkle]

Re: Motor idle.

Perhaps a vacuum leak, though they tend to stall the car out. I'm guessing the mentioned MAF seneor, it's probably dirty or broken. When my MAF broke, it had the same mentioned symptoms

[Leonard 3.8L]

Re: Motor idle.

Yea; my Dad and I were talking about vacuum leaks and we will check that. I've already checked my MAF and cleaned it. New EGR is probably next on my list.

[jimmysprinkle]

Re: Motor idle.

Are you throwing a SES code for the EGR? Try this: Unplug the EGR-to-Intake hose, and have someone plug the hole with their thumb. Try idleing the car like that. If the problem goes away, then it's the EGR. Don't want to replace unbroken parts though, haha.

[Leonard 3.8L]

Re: Motor idle.

Are you throwing a SES code for the EGR? Try this: Unplug the EGR-to-Intake hose, and have someone plug the hole with their thumb. Try idleing the car like that. If the problem goes away, then it's the EGR. Don't want to replace unbroken parts though, haha.

Exactly; my sensors were toast though. It's still throwing SES codes. My best bet would probably be to get it scanned. I know I have never changed my EGR ever.

[ssms5411]

Re: Motor idle.

When cold the HPtuner files have the idle at around 900-1000 RPMs once warmed up it has idle at 750 RPMs. But I would look at the IAC (idle air controller), or a small cracked vac. line with small laek.

[Mighty Thor]

Re: Motor idle.

This happened to my 89 bird and it was the EGR that was the problem.

[Leonard 3.8L]

Re: Motor idle.

This happened to my 89 bird and it was the EGR that was the problem.

I would have to agree with you; sounds like that might actually be the problem.

[Leonard 3.8L]

Re: Motor idle.

So I start my car and it sounds like it's sucking air. Best way I can explain it. We're going to bring it to a shop and have it worked on. Wish me luck.

[firebirddrvr]

Re: Motor idle.

good way to tell if its a vac leak is run the car, shut it off, and right away you shouldnt hear any more air. if you turn it off and hear a sucking of air noise...its a vac leak