Morning start up and idling issues

[Michael A 2]

I've been having morning start up and idling issues 80% of the time when I start the engine in the morning. Idling would be rough ranging from 800 rpm to 350 rpm as if it was about to stall. But I give it gas and it would go up to 1100 rpm and stay there until it goes back down to 750 rpm after a few minutes. After that, no more symptoms or idling issues throughout the day. Was wondering what may be causing this? Bad fuel filter? Bad fuel pump? Changing spark plugs? or a whole tune up? Truck has 85000 miles on it. Any thoughts or feedback would be highly appreciated.

 

[Dave S 2]

Could be all of the above but at first guess, I'd say unplug the battery for 30 minutes or so and touch the + to the -.



I say this because I have been visited by the ST gremlin and the battery thing seems to cure it for months at a time.

Good luck...

 

[Michael A 2]

Thanks Dave for the response... tried that before but didn't work. Looks like I may have to perform a fuel filter change, & spark plug change. If that don't cure well it's probably the fuel pump. Hard to pinpoint the source of the trouble.

 

[Rodger Tellefson]

The Idle Air Control motor could be part of the problem. Do this project, and if it helps I would go ahead and replace the IAC because of how many miles you have on your ST.

 

[Michael A 2]

Thanks for the feedback? What is the part number for the Idle Air Control just in case it needs replacement?

 

[John Bartman]

Can anyone tell me approx. price on a new idle air control thanks