93 explorer sport starting issues

[SFCRangerDoc]

UPdate:

Sorry for the large gap. I went on call for my work and have not had any time to work on that stupid car. The sea foam cleaner has been added to the tank and it seems to have smothed out the idle and all that but has made no change to the starting of the car. This morning i cranked it for a good 5-10 seconds...nothing, key off, cranked it for another 5-10 seconds while pumping the gas pedal...nothing, key off, cranked it again and it acted like it wanted to catch and did for like .5 second and then died. 4th crank it finally started and i was able to turn off/restart multiple times w/out issue. its just when it sits over night or all day that it has issues. I am attempting to source an ICM to try and a MAF to try. Not many wrecked ones right now to choose from. Car has really nice power now that I've changed the plugs and wires and fuel filter! Really snappy throttle!

 

[natenkiki2004]

I haven't had my coffee yet and forget if you tried this but turn the key on & off (on, wait, off, on & repeat) several times, letting the fuel lines prime up then try to start.

 

[SFCRangerDoc]

I haven't had my coffee yet and forget if you tried this but turn the key on & off (on, wait, off, on & repeat) several times, letting the fuel lines prime up then try to start.

Yeah I try that too...doesn't seem to matter much. I'm really leaning towards the computer now not the fuel pump. MAF errors (which ive seen some in the flash codes) are often hand in hand found with computer dying. From what I understand from research the ECU controls spark and all that at inital start up and once the car gets running its handed off to the ICM. I have a test lined up for this weekend. My sister has a 93 Exploerer 4 door 4x4 and I am going to borrow the brains out of it and try them in my wife's sport. Same engine and all that just no 4x4. I figure if I put it in, and let it sit over night and it fires right up I know what the problem is. Otherwise its fuel pump replacement time...

 

[natenkiki2004]

I think you're right but the other way around. The ICM provides base timing and the ECM takes over once above a certain RPM.

If you get bored, I found all kinds of good info in this Ford Fuel Injection book:
https://dl.dropboxusercontent.com/u/464376/vehicles/1991 Explorer/Ford_Fuel_Injection_Book.pdf

It talks about the early fuel injection including ours.

 

[SFCRangerDoc]

I think you're right but the other way around. The ICM provides base timing and the ECM takes over once above a certain RPM.

If you get bored, I found all kinds of good info in this Ford Fuel Injection book:
https://dl.dropboxusercontent.com/u/464376/vehicles/1991 Explorer/Ford_Fuel_Injection_Book.pdf

It talks about the early fuel injection including ours.

Thank you for the PDF! I will put it on my tablet and have some "throne" reading material.

And I may very well have gotten that mixed up. I've been reading so much stuff about this car and some of it on forums is contradictory and confusing. Regardless I will maybe take the ICM out of my sisters explorer as well and test both...if it still wont crank then I've got one other thing it could be...the fuel pump. But I struggle with the fuel pump because it runs fine when it gets running...

 

[natenkiki2004]

In all fairness, I could have that backwards as well. I forget which way it goes but it does work as you describe, there's a hand-off.

I'd buy a fuel pressure tester before dropping the tank. If it shows the right pressure then you have no reason to believe that it's the problem.

 

[SFCRangerDoc]

In all fairness, I could have that backwards as well. I forget which way it goes but it does work as you describe, there's a hand-off.

I'd buy a fuel pressure tester before dropping the tank. If it shows the right pressure then you have no reason to believe that it's the problem.

I have one...it shows mid 30s PSI for fuel and does hold pressure for a good long time after shut off. I'll toss it on there again for good measure though and double check.

 

[natenkiki2004]

I have one...it shows mid 30s PSI for fuel and does hold pressure for a good long time after shut off. I'll toss it on there again for good measure though and double check.

Sounds good to me, I'd look elsewhere.

 

[SFCRangerDoc]

Had an frustrating morning with this POS car...I went out to start it like i normally do for my wife so that she doesn't have to mess with the cranking BS. Got it started and all that, shut it off, restarted it a couple times just to make sure it would restart ok...went ok cool its GTG and went off to work. Wife went out less than 20 mins later, could not get the car started no matter what.

 

[mr cribb]

You might on to something with the fuel pressure.

I had a 97 Chevy truck years ago and I couldn't start it for nothing. Checked pressure and I was a 58 psi, and the specs were 62 psi for minimum. New pump solved the issue.

 

[mr cribb]

http://www.explorerforum.com/forums/showthread.php?t=170334

Fuel pressure thread

 

[SFCRangerDoc]

Interesting thing this morning...i heard something I have never heard before coming from under the car...I got it running finally but then heard this gurgling/bubbling sound...sorta like somebody was blowing bubbles through a straw. I think it was coming from the fuel tank but I didn't have time to get under the car and pinpoint the actual location. Is this something any of you guys have heard of before?

Also on the topics of fuel pumps, are there any brands to stay away from/better than others?

 

[2stroke]

Clogged vent line for the tank

 

[SFCRangerDoc]

Clogged vent line for the tank

so nothing related to the fuel pump per-se? and that wouldn't cause my no-start situation, right?

 

[mr cribb]

This link is for the 1st generation. I didn't realize the other link was for the 2nd generation.

After reading the first page of the thread, one poster mentioned replacing the fuel pressure regulator.

https://www.explorerforum.com/forums/showthread.php?t=142801

 

[FR-425]

The gurgling you are hearing is the fuel returning to the tank, way to much fuel returning!

The fuel regulator is bypassing the fuel rail and sending 100% back to the tank.

OR. The fuel pump is ingesting air. Air in the fuel line will also cause the FPR to bypass.

I would replace the FPR first. If the problem persists then I would say the hard line inside the tank has failed, the pump is running but some of the fuel is just spraying back into the tank and also picking up air and sending it up to the FPR.

Probably time to drop the tank anyhow. It is 22 years old. .. ..

 

[2stroke]

He already replaced the FPR. I've had the gurgling sound, and my vent line had plugged. I vented to atmosphere, to solve the problem. A leaking connection, or pinned/broken fuel line could do it too.

I should mention, when the vent line plugged, I got a big hissing sound when I took the gas cap off.

 

[SFCRangerDoc]

He already replaced the FPR. I've had the gurgling sound, and my vent line had plugged. I vented to atmosphere, to solve the problem. A leaking connection, or pinned/broken fuel line could do it too.

I should mention, when the vent line plugged, I got a big hissing sound when I took the gas cap off.

Yeah i dont get any hissing sound on the gas cap. My sisters expy does do that though. I thought it could be possibly picking up air in the tank and then air getting in the lines and the FPR returning the bubbles back to the tank. I'm doing my computer/icm test this weekend and then my course of action will be to drop the tank and replace the pump if that doesnt resolve it.

 

[Rhett]

Probably time to drop the tank anyhow. It is 22 years old. .. ..

You know that raises a question. Since we have plastic tanks, I'm assuming they should be good even after 20+ years.

I'm assuming ethanol etc. etc. won't destroy the plastic, as surely by 91-94 auto manufacturers were using tanks suitable for ethanol, right? If that were not the case, my tank would have failed long ago. Am I right on that?

So, what other reasons would there be to replace a tank? Varnish buildup?

 

[mattZ]

I have this exact (I mean exact) problem with my 96 sport. I cleaned and tested all the sensors and still have the problem. It's intermittent and after about 10 seconds it starts idling normally. I talked to a mechanic/friend who said even though the IAC valve is cleaned/opens/closes and tested fine, it could still be bad. He said it's a huge problem with this year range of fords. Not sure if this is the problem, but I'll be ordering a new IAC valve soon.