Very true ChrisBennet; I have same issue and now it has just hit winter here, with the engine cold, the rev's would drop so low the engine would sometimes stall; Steve Wong suggested to bring the base idle up another 50rpm which I did. This raises the threshold where the 'computer' can compensate to suit.....

This still doesn't fix the main problem which is probably an iffy ISValve.

Re vacumm leaks; tighten the intake manifold gaskets down too.
Replace any cracked breather hoses.

...then rebuild top end!

So it sounds like, on a 3.2 if your idle does not correct itself with the oil cap off, you have a problem?? Is that correct?

Yes.
-Chris

But there's still a bit of time lag until it corrects itself, say half a second. Right?

Thanks http://forums.pelicanparts.com/ultim...ons/icon14.gif

Yes, there's a little dip in the idle before it corrects.
-Chris

Nothing to contribute here: just learning. Thanks all!

Steve,
You're certainly entitled to your opinion, but my opinion is you were certainly and inappropriately harsh on Bernie (einreb) for what amounted to silly, playful banter on his part. All in good fun, you know.

Edward

Quite interseting this topic ,

i've posted mine yesterday, with the reverse problem : car does not turn ok (idling) with cap on , with cap of perfect.
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Originally posted by 87coupe
So it sounds like, on a 3.2 if your idle does not correct itself with the oil cap off, you have a problem?? Is that correct?
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so , I don't have a problem if I see this !

remains to find out why it does not run with the cap on ! :rolleyes:

bye

GrowIt, how long ago did you install the new chip and was it after your previous oil check? Your stable idle is probably the result of the modified and much superior idle coding of the new chip. It has the ability to smooth out O2 sensor hunting and even mask what idle instabilities that occur at cold starts, or caused by air leaks, worn sensors, lightweight flywheels, more aggressive cams, and idle mixtures that are just a bit off adjustment. The code autocorrects and guides the rpm to target naturally within a few engine cycles, and controls the speed of rpm drop to give the ISV time to adjust, eliminating sub idle dipping. You can reinstall the stock chip if you want to trace what caused your rough idle before.

GrowIt: you are correct on tthe engine should stumble when the oil cap is removed.

Here are a few things to methodically check prior to replacing components:

1. Re-torque your Manifold bolts..There are 12 of them with an 8mm hex head, torqued at 18ft/lbs...Make sure you get them all. You'll need a universal socket attached to your 8mm socket to get to all of them.

2. The manifold boot...Connects the right and left halves of your manifold. Remove the 2 clamps and slide the boot back and forth to clean the lips where the boot clamps down on. Patience with this as the boot will expand once you remove the clamps but, you can get it back together.

3. there is a hose running from the oil filler neck. Inside that hose is a restrictor valve. Make sure that hasn't slid up into the hose. Pull the hose off and re-seat that valve onto the neck and re-install the hose.

4. Behind the throttle body you have several hoses and lines as noted in the diagram posted earlier in this post. Check them.

Re-post after this is completed....

It is a problem for the reasons Bill Verburg stated. If you open the lubrication system and aren't getting an rpm change, then you have free air, which is also unfiltered air, entering your intake system.

If you have a lot of miles, say 80k plus, then you may have a dirty Idle Control Valve. My BMW's have the same part on them, the 325i was filthy inside, cleaning it with Brake Cleaner restored it to operational status. You can take it off to look inside, and move the valve gate around with your finger as you spray it off. Now might be a good time to replace the hoses connecting it to the intake system as well.

Re: Re: Re: Oil Cap Removed No Engine RPM Drop Anymore??
 

WOW...that's harsh for a "Part-time Pelican." Lucky for you Bernie has a cool head and will brush it off.....

I guess he didn't listen to his mother?

SteveW
I got the chip about 2 - 3 years ago. It may have stopped the rough idle then. I was focused on checking the oil this time & relized it was not running rough (wife not around nipping at heels about this, that and the other thing). I do have the stock chip and may try that. I knew it ran rough with the cap off years ago when you focused on everything with the car (even the simple task of checking oil).

No harm done with the comment/answers. I have been lurking on this forum for a few years now and know what to expect. In addition, I can bust chops with the best of them too - when needed.

Thanks to everyonel for the suggestions. Once again, you can count on this site for answers to strange questions.

Kevin

Re: Re: Re: Re: Oil Cap Removed No Engine RPM Drop Anymore??
 

I apologize for the vulgarities, they were not appropriate and they are not my usual repertoire.

I like a good joke as much as anyone. In perspective, forum participants have broad rangers of knowledge and also a lack thereof. Some can rebuild the entire car and others are struggling with their first oil change. My point was when someone asks a question, it's because they don't know something and the assumption of the poster in a "humorous" response is that ***everyone*** knows the notion of muffler bearings, snipe hunt or whatever is obsurd. I have seen people belittled for asking "stupid" questions and have read the muffler-bearing thing far too often as a sole "answer" to someone's question. Guess I unloaded on Bernie in an inappropriate way and I apologize for that. I do however stand by the substanceof my post. I am far from a part-timer, btw.
regards,
Steve

Sounds like someone's been on a snipe hunt recently...

:)