2000 4.0 sohc won't idle

[zoomee]

2000 4.0 sohc.....truck won't start without giving pedal, won't idle, runs ok with pedal pumped. spark, vacuum check OK. Used to do this once or twice last few years, would idle ok after start.

Cleaned MAF as suggested.
Disconnected batt 10 min as suggested.
Have code reader on order.

 

[Black Magic]

Sounds like IAC, Idle Air Contorler.

 

[izackary]

Check your lower intake manifold gaskets. There was a Technical Service Bulletin on those. Take it to the dealer and they should replace them free of charge, as well as possibly change the cam chain tensioner since it's close to the gaskets. Unfortunately I have a high mileage truck so I don't know yet if they'll do mine free or not. Until I do mine, I can't tell you how my idle changes when i get new gaskets in.

 

[canada74]

what about the t.p. sensor?

 

[izackary]

yeah, try cleaning the IAC valve with a q-tip or something as well as the TP sensor first. the lower intake manifold takes a while to get off.

 

[zoomee]

it was a bad IAC, all fixed now..thanks.

 

[izackary]

good call. what was bad? was the IAC valve itself bad? dirty? stuck? what?

 

[The"X"]

My 2K does that intermitently. It either happens at start up or not at all. Never happens in the middle of a drive. It did it two days in a row right before I took it to the dealer on Monday, but wouldn't you know it, it did not do it the whole time the dealer had it. Nothing showed up on there tests. They just did the 00M12 last week on it.

 

[crazybill]

mine did it this weekend at the dragstrip . it was the first time i had towed with my 95 sport 4x4 so i assumed the truck just doesnt like towing . after it sat a few hours it started and idled just fine . going hom that night with just the empty trailer since i left the bikes at the track it didnt seem to mind a bit . the bikes are MAYBE a thousand pounds between them and the trailer was just a wood decked open 6x10 .

yesterday for the second time since i bought it just a few weeks ago it did some bucking thing going down the road at about 40mph . wonder if the problems are related . it was like it was running out of gas .

 

[Nate1]

Mine just did it on a looong trip to NC. I knew what it was right away, went to the nearest parts dept, and fixed it in a grocery store parking lot in 5 mins.
Now my truck idles like a normal one should too .... thank god!

 

[shum]

NWIEBLY - what part did you buy and replace in a parking lot??