01 Exp, start and stall

jman2469 · 08-03-2008, 06:41 PM

Hey ppl, so this just started happening like a week ago and its not constant. When startign the vehicle it cranks over and starts and will instantly quit running, but at other times it starts up and idles fine, and other time it will be a extermely low idle. When it does not act up the vehicle runs and idles fine. Upon having to go somewhere and it was doing the start die routine, I played the keep one foot on the pedal to keep rpm and brake drive for maybe a time of 5 mins and when took foot off gas it would idle fine. I was thinking of possiple TPS gone bad or MAF(P) sensor, possible IAC just wondering if anyone has seen this particular problem and what was the possible fix for it

microsfoftxpuser21 · 08-03-2008, 06:56 PM

change the tps then check egr map sensor then mas air flow sensor these r the 3 colprites for normail engine idel so yeah those could be reasons for stalling each run cheap autozone.com your best bet plus cheap on price

jman2469 · 08-03-2008, 07:24 PM

Well as far as MAP and MAF, I'm pretty sure most vehicles do not have both. plus isn't the MAF more directly related to a/f ratio then idle? And as for MAP doesn't it more directly relate to like the differences in altitude? cuz im at the same altitude. Egr has nothing to do with the idle as far as i know

microsfoftxpuser21 · 08-03-2008, 08:45 PM

well change the tps sensor and next would be idle air control valve located on top of the intake i've been hard at work today on my car so yeah change the tps then if it start and tries to idle then stalls then definitely iac valve is bad if it original they go after 60,000

navyredman · 12-02-2008, 06:17 PM

Quote:

Originally Posted by jman2469

Well as far as MAP and MAF, I'm pretty sure most vehicles do not have both. plus isn't the MAF more directly related to a/f ratio then idle? And as for MAP doesn't it more directly relate to like the differences in altitude? cuz im at the same altitude. Egr has nothing to do with the idle as far as i know

seeing as I just bought my expedition yesterday I don't know the direct answer to the EGR question on this vehicle. However on most other vehicles the EGR valve will effect idle greatly, also tranny shift points and gas mileage

theoldwizard · 12-03-2008, 07:35 AM

Quote:

Originally Posted by navyredman

... on most other vehicles the EGR valve will effect idle greatly...

If EGR is "leaking" in at idle you are correct !

Typically EGR fails "off" (no EGR flow)

navyredman · 12-03-2008, 04:42 PM

Quote:

Originally Posted by theoldwizard

If EGR is "leaking" in at idle you are correct !

Typically EGR fails "off" (no EGR flow)

I am actually working on an Isuzu Rodeo that has an EGR valve that is stuck off and it makin the idle really bad and making the tranny shift HARD!!!

Like I said before, I don't know much about the expedition, but my friend that is an ASE tech told me we can take it off and clean it real well in a parts cleaner and see if that helps, otherwise I have to buy a new one for $169

I really don't recomend cleaning anything electronic in a parts cleaner unless you know for sure it's bad and the only other option is to buy a new one.

The other option is to take the egr valve off and clean out the carbon build up with a brush being careful to keep any debris from getting into the valve. Another thing to check for, is if the EGR valve has failed check for carbon build up on the throttle body. Clean that out and make sure to get all debris out as well. getting the debris out is EXTREMELY inportant because if you don't it will be ingested directly into the motor