01 Sport Trac starting troubles

[monkeydude3]

Hey everyone, it has been a while once again. School and work have me busy as heck, and I bought an 82 Mustang that I'm restoring...

Anyway, my mom has a 2001 Explorer Sport Trac with 4X4, automatic, 4.10s, all the bells and whistles. Only "mod" stands as a HeartThrob cat-back exhaust kit. (BTW if you want a sound clip let me know). It has about 103000 on the clock. Does not burn a drop of oil and has never skipped a beat before.

The problem she has been telling me about now is on cold mornings when she goes to start it, it will stall 1-3 times and she will have to re start it and after the 2nd or 3rd time it stays running.

Now... when we bought it, I insisted that the truck be tuned up completely. I checked, they did plugs and wires.

Recently I put a fuel filter in it, air filter, seafoamed it completely, and changed the trans pan gasket and filter. When I did these, I also took out the IAC and cleaned it completely and also cleaned the throttle body. I did these all at school with the little throttle body cleaning kit. We also ran a "MotorVac" treatment on the engine/fuel rail at that time. This is all within 5000 miles of now.

Other than regular oil changes (every 4000 +/- 500 miles) of Motorcraft synthetic blend, we haven't done much to it other than keep it clean.

Any ides what to check next? MAF? I was thinking I'll hook a fuel pressure gauge up to it and see what we have, because perhaps the pump is getting weak and/or the regulator.

Any information will be much appreciated.

Thanks much!

 

[brianjwilson]

Sometimes cleaning the IAC valve can make it worse, maybe by dislodging something in it. That happened with my Ranger anyway. No CEL codes I'm assuming?
You might be on the right track with low fuel pressure.
The other thing I thought about was a vacuum leak in the intake manifold or something. I know it's common for the intake plenum gaskets to go bad, but I'm thinking that normally causes a higher idle, not stalling.
Try unplugging the IAC and starting it cold, see what it does...?

 

[sporttractuner]

Hey guy, I had this problem once or twice, but not regularly...let me know what you come up with....that fuel pump thing might be something...I notice that my power window motors suck pretty bad when its cold out...is a fuel pump so different?

 

[monkeydude3]

No codes, no check engine light. I'm going to hook up a fuel pressure gauge to it sometime this week and see what we have.

I worked at a Ford dealer as a driver for about a year and in that time I saw more fuel pumps going out on trucks than I knew was possible. Many many explorers too.

And they all started by doing the thing it does now, start, stall, start, stall, start run. Because each time you are building up the pressure. The end result is you will drive somewhere, come out to start the truck to go home and she won't fire at all.

As for the intake leak... we have no lean codes, no misfire, no high idle, idles nice and low. Once it's running this thing runs like a brand new truck!


I'm at work right now, but as soon as I find out something I will let you guys know. Thanks for the help!

 

[Joe Dirt]

Yup- brianjwilson echo's me- I've cleaned many IAC's in my past cars. Some run awesomely flawless afterwards, some run like crap, continue to run like crap, and I've had to replace the valve- which solved the problem every time.

 

[monkeydude3]

Before I condemn the IAC I will check the fuel pressure...

but would a bad IAC cause this issue?

 

[brianjwilson]

Before I condemn the IAC I will check the fuel pressure...

but would a bad IAC cause this issue?

When mine went bad, it didn't die on start up I don't think, but would randomly idle VERY low and stall when I came to a stop and depressed the clutch. And of course the "fog horn" noise on warm days that came first.
The fact that it only does it when it's cold makes me think it might not be the IAC valve.

 

[monkeydude3]

When mine went bad, it didn't die on start up I don't think, but would randomly idle VERY low and stall when I came to a stop and depressed the clutch. And of course the "fog horn" noise on warm days that came first.
The fact that it only does it when it's cold makes me think it might not be the IAC valve.

My dad had an Aerostar van... with the 4.0 OHV... but it did that 'fog horn' thing you described, but we were trading it in so I never replaced the IAC...

Well the past few days it has not done it. It has been spurratic.. I will find out if it is on cold days, or extremely cold (below freezing) days. We have taken good care of it so I would hope it's nothing radical.

I also need to use it Monday to haul a transmission and then pick up some interior stuff!!

Thanks for the input guys. I've been so busy with work, school, and the fire department I don't have much time to think.

 

[sporttractuner]

my brother had a fuel pump go on him a couple of years ago...he said that if you have s0omeone listening by you're tank when you try to start it, it whines pretty bad right before it goes...
my truck started on the second try this morning...why is the always some little hottie near by....