1999 Ford Expedition Q&A
1999 Ford Expedition Question: High Idle on start up
I was getting high idling while driving not while starting up found that the Trottle Sensor was bad again ,I had replaced the Trottle Position Sensor and Idle Control Valve back in March 2013 due to rebuilding just put everything new. I'm now getting a high idle when starting up after replacing Trottle sensor again. Would it be the Idle valve to again. - 915tommyboy74
Possible vacuum leak. - pushrod
agree with pushrod or tps is misadjusted - globalhelper
You may have a vacume leak causing the fast idle. Also have seen a stuck PCV valve cause this a few times. - milesauto
The mass air flow sensor (MAF) may fail resulting in a rough engine idle, hesitation on ac...