Need Help Guys ?????

[1970dodgecharger]

I know this is not a dodge question but anyway here I go.  My Ford Explorer one day just decided that it did not want to idle anymore.  I have changed the MAF airflow sensor, the TPS sensor and the air bypass
valve all to no avail.  I have talked to ford dealership mechanics and others who have told me a bunch of things pretty much all of which I have tried.  I was also told that it could be a vacuum leak.  There is no noticeable vacuum leak although I know it could be hard to find.  Also I thought it might be the MAP sensor but I cannot for the life of me find it on this 4.0 l motor.  I can drive the vehicle if I two foot it and after it gets off idle it runs fantastic just as before.  Please guys I am out of ideas and I really can't afford to
go to the dealership at $95.00 an hour.  HELP ME !!!!   thanks  Allan

[Chryco Psycho]

it has to be either air or fuel related , have you checked fuel pressure , possible that one of the connectors has a bent or corroded pin or just isn`t plugged in fully ?
unbolt the throttle body & look to see if the AIS passage is plugged or the gasket is bad

[RD]

the air intake hose may have dry rotted causing holes to rip into it thus causing air to enter into the engine that is not being accounted for by the MAF sensor.

[1970dodgecharger]

The air intake hose is good no tears and as for the fuel  sending unit including pump is 2 years old and one of the first things I did when this started this whole thing was change the fuel filter.  I have never checked
the fuel pressure but like I said after you get off idle she goes perfectly even under hard acceleration.  Does anyone know where I would find the MAP sensor and could this be the problem.  Also could this be a computer foul up.  Like I said before one day it was fine the next it was not this was not something that just came on over time.  THANK YOU AGAIN  Allan


I have posted a picture of what the MAP sensor looks like but do you think I can find It.  One of the only places I have not looked is under the battery tray....  any ideas ?

[1970dodgecharger]

Also what do you mean by an AIS passage?

[palindromes]

My first guess would be your idle air control valve is sticking.  It's a pretty common problem on fords & causes the exact problem you describe (engine runs fine, but won't stay at idle speed).