Hi. I have been experiencing some problems with my 2000 expedition 4x4 4.6L, sometimes it wouldn't start normally, it would start up fine but idling is at 400rpm and then I would need to slightly just press the gas pedal because once I push it hard and then let go it will die, i will also need to be careful of hard braking it will die. But then after a while (maybe a few meters of driving, like maybe 100 meters it would go back to normal idling and everything goes back to normal, when its in abnormal mode (hehe) the a/c will not get cold as if its just in fan mode.

Also is it normal for the idling to go down and then up again after you open the gas cap when you fill up with your engine running?

I have seen posts telling its the IAC valve but how does that look like ? If anyone has a pic of that in their 4.6 and where to locate it, please help me.

My truck would start normally every morning, but in the morning when I start it sometimes it would start and then as if it would die off right after i start it , RPM would go high and then go down as if its gonna die and then it would go back up and then normal idling.

Please help...

 

Please help!

 

Since you said please ..

You should search this forum , the IAC pics are easy to find. Theres two locations , ones in the back and the others on the side of the throttle body.

Your IAC is stuck closed.

This ones in trhe back -





Theres three in this pick -




Heres a link that shows it as well , this will show you a side mount IAC , click the link below -

http://www.fordf150.net/howto/throttlebodyclean.php

BTW - Sometimes you may free them up temporarily by knocking them on the housing with a broom handle..