Hey guys, at start up whether the engine is hot or cold the engine will run at a high rpm's for a minute or so then comes down to 700 ish rpms. Is this normal or do i have something that has gone out? There are no codes. Thanks for the input. Really this is not a big deal. Just wanted to see if there is a fix for this.

Could it be the IAC? Would it not throw a code if it is?

 

it is normal

 

Thank you!

 

Depends on what you call high RPMs. If it's around 1200 then that's normal, higher than that is not.

 

I do not have a tach. So I use my computer/diagnostic tool to look at the live data. I will check it next time I drive it. Thanks

 

It pegs out around 1700 rpm at start up.

 

Yeah that's a bit much. I'd try checking for vacuum leaks then cleaning or replacing the IAC valve before doing anything else.

 

Ok Thanks!

 

Started driving my son's 98, 5.4L, F150 a couple weeks ago due to playing musical cars at my house. It does the same thing, but per the tach, it hits about 1575 to 1600 rpm's. Son said it has been doing this for quite some time. I don't drive it very often, but I don't remember it doing that. No other codes or issues. Will follow this thread to see if you find anything 02GPS.

 

I think there is a way to clean the IAC right?

 

Here is a DIY post.
https://www.ford-trucks.com/forums/9...4l-triton.html

 

Thanks a ton

 

Sent u reps not sure if it worked

 

It did not, but don't sweat it.