Cold weather idle?

[gyates]

So I am throwing this out there to see what other Gen. 1 'Trac owners are experiencing. In cold weather, ambient temp. below 40, where does your truck idle? Mine idles around 600. Above 45 degrees idle is 750. Is this normal?

 

[Taylor Corn]

Just going off my gauge those seem to be about right. Are you measuring this with a scanner or just the gauge?

 

[gyates]

Bigt, I am using the tach. It has always idled this way since I purchased it over 5 years ago, but I have never thought that large drop was correct. Maybe it is.. I know on my wife's '04 Explorer there is almost no difference in idle regardless of the season or even if the a/c is on or off. It always idles at an indicated 750. I will add, on my 'Trac, when it is "warm" enough outside for the compressor to kick on the idle will rise to 750, but when cold enough the compressor is basically never running then 600-650 seems to me the idle on my truck.

 

[Yardsale]

The engine management system should keep the idle the same regardless of ambient temperature and whether the (A/C) compressor is on or off.



It seems that some variation is okay, but 600 seems low.



My '01 idles at what I think is low ~650 and it is sometimes slow to shift from reverse to drive and vise versa. Because of the engine management system, I'm not in the habit of fiddling with the idle and am kind of waiting until something breaks that will explain the low idle. Of course, this may not happen.



This noted - maybe ... this is a sign of an older engine (245,000 miles) that needs a little idle adjustment help??

 

[Taylor Corn]

When I've had issues with hard starting/poor idle problems, usually it has been too long since I've removed my MAF sensor and given it a good cleaning, maybe try that and see if you achieve any results? Could a dirty IAC valve be the problem here also?

 

[Yardsale]

IAC problems typically present as rough idle, but not low.



These two items are quick, easy and inexpensive. Might as well try them.

 

[gyates]

Thanks for suggestions Bigt and yardsdale. The IAC is relatively new to solve a high idle issue and the MAF has been recently cleaned. I have always thought something was not quite right with my system since I see this low idle issue every winter. I don't have any scan tools so I do not have the ability to see what may be happening, but I put this thread up here to see what others see with their Gen. 1 'Tracs. My truck has 111k miles on it and has been maintained as the owners manuals suggests. Fortunately I do not have any other symptoms, just the low idle with cold ambient temps.