High start up idle

[blacksambo]

One of our '99's has decided, out of the clear blue, to jump to a 2000 rpm idle on cold start and then settle down to 750rpm after several minutes. Does anybody know what might be causing this and how to remedy? Thanks.

[Tobert]

That sounds like a coolant temp sensor to me.

[Jolly Roger VX'er]

Personally, I would unplug and remove the IAC (Idle/Air Control) Module located on the side of the throttle-body (not the throttle position sensor!) and check it along with where it resides in throttle-body for carbon build-up. You might just have to spray sensor-safe carb/throttle-body cleaner to flush out both module and inside TB. Re-install and see how she runs. If not better, might want to invest in a new IAC Module as they sometimes go bad. After that you might want to look into intake gasket leaks or vaccuum leaks. Really sounds like the IAC Module to me though.

[blacksambo]

Many thanks for the insight; I'll check these areas out pronto.

[SPAZZ]

my 2001 Ironman(now a line-x'd Black Ironman) did this for quite a while.

Poor hard to no start for several tries. Sometimes opening the gas tank lid after a couple no starts and then closing it would allow for a start. Sometimes not. If not I would have to hold my gaspedal down while starting then shift into gear without letting off. After this problem it would idle extremely high like 3,000 Rpm or start and idle really low almost to dying point.

I just changed my Fuel Pressure Regulator and it Idles much more normally(around 1,000rpm) now and starts very easily(one try and smoothly) and normally. No more hard starts, yet or Idle issues, yet. Hopefully it stays that way and improves mileage.

[blacksambo]

Thanks for this insight; I'll look into this as well.