Polishdog

Anyone had this on their 5.4? Mine is a 2001, only happens when cold, otherwise, runs great.
I remember reading a thread about the intake bolts? Is that possible? Can't find that thread now.

02_Black_On_White

When's the last time you had the TB off and cleaned? Sounds like your IAC is sticking. On the back of the intake behind the throttle body, almost to the fire wall you'll see it held in with two bolts. I'd take that off and see how gummed up it is. You may be able to clean it, but Its almost always easier to replace it.

Polishdog

I just got the truck, so I never had it off. It's it a good idea to remove the TB?
I will check the IAC.

02_Black_On_White

Could probably use a cleaning. But I'm saying iac is sticking.

Polishdog

Replaced the iac, still fluctuating idle, only when cold. Also p0171, p0174.

mandingo32

Check for corrosion on the PCV valve assembly maybe?

Polishdog

I can check, don't really see how that could affect idle.

mandingo32

It did with mine. I found a hole in one of the elbows.

Polishdog

Mine only does it when it's cold, if it was a hole or leak, it would probably do it all the time.

Jbrew

PCV/IAC always. If it only does it when cold. A new IAC won't make any difference. It's the PCV that's causing the IAC to func up.