1998 explorer died, won't start

[cb75]

Im just going to through this in here, i didnt read all of the threads but i just had one at my shop with this problem and it was the idle air vavle, also i had one with this problem and it was a plugged cat. Im not by any means diagnosing your vehicles just giving you some infor to consider.

Thanks, I appreciate any and all information or tips I can get.

 

[2000StreetRod]

IAC valve

It certainly won't hurt to clean the IAC valve but I don't think that's the problem. The vehicle starts with the fuel pump relay removed. If your IAC valve were bad, it would still be bad when the relay is removed. Also, you temporarily inserted a spacer between the throttle stop and the adjustment screw which opened the throttle to allow airflow comparable to what the IAC valve would.

As I said before, now that the engine will start and run it would be very helpful to read the diagnostic trouble codes that occur after replacement of the CKP sensor.

 

[cb75]

Well the fuel presure checked out OK, I have about 37 psi at idle. My haynes manual says it should be 30 to 45 psi. I'm going to go buy a code reader when I get off work tonight.

 

[cb75]

No luck yet, have been running behind schedule. I am stopping at O'rielly's in the morning to purchase a code reader and some MAF sensor cleaner. I was able to do some more checking last night and tonight- found that I need an alternator- mine is putting out 29volts at idle!!!! Perhaps this high voltage fried something??

 

[2000StreetRod]

Get it tested

It's hard to believe that a 12 volt alternator could output 29 volts. Are you sure of your reading? I suggest that you have it tested before replacing it.

 

[cb75]

Well, I got my alternator situation staightened out, I had a spare at home which I had checked out and then put on the Explorer. Re-checked charging system and it is now working as it should. So now I'm back to the original problem. Checked for DTC's and had only one- P0171 which my book says is "system adaptive fuel too lean (bank one). After searching the forum for this code, I found that this could be related to intake manifold gaskets? Could bad or leaking intake gaskets be causing my problem?

 

[2000StreetRod]

Leaking lower intake gaskets

The SOHC is notorious for the gaskets between the heads and the lower intake manifold leaking. In cold weather cold starts the engine speed will flare. First check for other leaks in the vacuum lines by spraying them with a cold engine with starter fluid or some other aerosol. See Starting my 00M12 Installation

 

[cb75]

After running out of things to check, I decided to pull the upper intake manifold where I found that the ports going to the right side of the engine are soaking wet with gas and the left side is dry as a bone. I'm starting to think perhaps I've got a timing problem? I have had a lot of chain rattle for some time. Is there any definite way to check timing on these engines?

 

[2000StreetRod]

Lean & wet?

The DTC says Bank 1 (passenger side) side is lean but you found that the upper intake manifold on that side is wet - with fuel? You earlier learned that you can start the engine with the fuel pump relay removed. It is possible that the diaphragm in your fuel pressure regulator is cracked allowing fuel to leak into the attached vacuum hose that goes to the upper intake manifold. That's the only way I can think of that fuel can get into the upper intake manifold.

Do you have access to a hand vacuum pump? If so, you can attach it to the fuel pressure regulator to see if the diaphragm will hold a vacuum. If not, you can disconnect the vacuum line from the fuel pressure regulator and cycle the key on/off a few times to pressurize the fuel system. If fuel emerges from the vacuum port of the fuel pressure regulator then you've found the source of your problem.

 

[cb75]

I do have a hand held vacuum pump, I will try these tests you mention this evening. Thanks

 

[cb75]

Well, no luck, I checked the fuel pressure regulator, removed the vacuum line and cycled the key numerous times and had no gas come out. i traced the vacuum line from the FPR to the manifold, it goes to the right or passenger side which feeds the left side of the engine which is dry. Is it possible that it could be out of time, injecting fuel on the wrong stroke, which is then forced back up into the intake manifold?

 

[cb75]

Now I'm really confused. I removed the lower intake manifold, and upon further inspection found that the rear most intake port on the left or drivers side is sitting plum full of gas?? Talked with a couple guys I work with and they believe I have either an injector issue or valve problem.... I'm gonna call it a night and tomorrow I'll pull the valve cover and see how much more bad stuff I can find!!

 

[2000StreetRod]

Suck out the gas

You should suck (not with your mouth) out all of the gas pooled in the port before cranking the engine. You can damage the valves if you have an incompressible liquid in the combustion chamber during the compression stroke.

I suspect that you have a badly leaking injector for that cylinder. I doubt there is anything wrong with the timing. With the rail pressurized you should be able to see the injector leaking.

 

[cb75]

Well, pulling the valve cover did expose more bad stuff, The rocker arm for the intake valve was laying beside the spring! Apparently the prevoius owner was not too crazy about maintenance, I've never seen such a filthy engine. It looks as though the roller wasn't being lubed properly causing it to seize up and develop a flat spot which then allowed it to come out of where it should be. I'll try to get a picture if I can get my camera to work.

 

[panamexplorer]

I have a 98 4.0l sohc xlt 4x4 that is also having a starting issue, but may be from a different source as I just R&R'd the automatic transmission.

Should I start a new thread or continue on this one as they are basically the same problem?

 

[2000StreetRod]

please continue

Since you've already revived this thread you might as well continue.

What is the history (died while cruising, etc.) and what are the symptoms (cranks but won't start)? Also, what have you tried (checked fuel pressure, replaced spark plugs, DTCs, etc.)?