Help/ I should write a how NOT to book

[raceace73]

Hello I've been having problems with my 94 ford ranger 4.0l v6. At first it would just start to sputter and cut out all of a sudden with temp. not seeming to be the trigger. I have been fighting this battle for months. It was so intermittent that it was hard to track, finally it would not run the pump one day at all. I changed the pump and started it up and it ran great, then I put the filler neck on and lowered it off the jackstands.after I lowered it down it ran then started to cut out again. I can start it and it will run but not great. Sometimes it will die out. When it starts to die out I can unplug the Maf and it straightens out a bit. I have already swapped the Maf with one from a running truck though and another one as well. What else could be my problem? In the prior months I had changed the following:
Maf
Fuel pump relay
Fuel pump
Fuel filter
Throttle position sensor
Checked the inertia valve
What do u think could be wrong? If it is the ECM is it in the interior of the drivers side firewall that it gets pulled from? Any help is appreciated! thanks

 

[leftoverture]

Kinda sounds like a bad injector. Have you checked codes?

 

[raceace73]

Yes I tried to check them but one of the codes it threw was unable to complete "wot" wide open throttle. The other codes were tps which I switched, maf which I switched, and oxygen sensor which I unplugged and made no difference. If it were a bad injector would it straighten out when I unplug the maf?

 

[leftoverture]

If it were a bad injector would it straighten out when I unplug the maf?

I don't think so.

 

[huntman58]

If it’s the ECM and it’s like my 93 it’s on the kick panel pass side inside. Just pull that one Xmas tree pin and you can get at it easy may have to pull back the carpet some but nothing major.

If you could get your hands on a known good one I would just to try it and see. as the injectors are back fired meaning the ECM dose not control each injector but the whole bank this is why you can not do a cylinder balance test on a batch fire ECM.

From what you have posted and also by not being able to pull codes there is still one part in the fuel system that could do this and that’s the FPR. Check your vacuum line at the tee on the intake manifold and at the FPR . see if you have any raw fuel in it. If so you have a bad FPR. most times they fail to the point of flooding threw the vacuum line but I had one fail to were it cut fuel for some reason. maybe a blockage as the filter had not been changed in more then 150,000 miles. Any hoot check it for fuel in the vac line and also pull a fuel pressure test at the fuel rail and see what you have as low pressure will make it act like its starving and flooding will make it stumble and not want to run also when trying from a cold start. Even with new parts the new parts can fail or even be bad from the get go at times, this is why we always check thermostats before installing them. Good luck and let us know what you find on that FPR (Fuel pressure regulator)

 

[raceace73]

Ok thanks guys I will chek the fpr. How do I check the pressure at the rail? Is there as tester I need or could you tell from a discharge of fuel?
Thanks again I will get back to you on the fpr asap

 

[Roadrunner777]

You will need a fuel pressure tester. It is a good tool to own if you plan on keeping the Explorer. Here is the how-to thread with pictures:

http://www.explorerforum.com/forums/showthread.php?t=142801&highlight=1st+fuel+pressure

 

[raceace73]

When I get the fuel pressure gauge should I watch it until the engine starts to cut out or if I have sufficient pressure at the beginning will it stay that way. Also is there a special size regulator or are they universal?
Thanks

 

[Roadrunner777]

If you can get a reading when it is acting up, that's the ticket. Otherwise, just a reading with the engine off would say something. Read the thread I linked.

The fpr is specific to the explorer and not adjustable.

Stop buying parts, do diagnostics and buy the right part.

When you replaced the pump, did you flush the tank or at least have a good look inside? I don't mean to be antagonistic, I replaced my pump and just threw it in. I should have shined a flashlight inside to see what was going on. I got lucky. What did the old pump and strainer look like?

 

[raceace73]

No sweat at all I appreciate the help. I took a good look at the empty tank and it was clean and even the old strainer looked ok, just a little discolored. I replaced the strainer anyway and made sure the tank was clean. I also made sure to hit the top of the tank with pb blaster and wipe it off real well before I twisted it open.

 

[raceace73]

I don't see a tee on the fuel pressure regulator. There is just one braided line that goes into it. Is mine spring controlled rather than vaccum or am I looking in the wrong place? Also I borrowed my buddies pressure tester and the shreder valve appears to be smaller than the gauge. Is there a specific size adapter I need?

If it’s the ECM and it’s like my 93 it’s on the kick panel pass side inside. Just pull that one Xmas tree pin and you can get at it easy may have to pull back the carpet some but nothing major.

If you could get your hands on a known good one I would just to try it and see. as the injectors are back fired meaning the ECM dose not control each injector but the whole bank this is why you can not do a cylinder balance test on a batch fire ECM.

From what you have posted and also by not being able to pull codes there is still one part in the fuel system that could do this and that’s the FPR. Check your vacuum line at the tee on the intake manifold and at the FPR . see if you have any raw fuel in it. If so you have a bad FPR. most times they fail to the point of flooding threw the vacuum line but I had one fail to were it cut fuel for some reason. maybe a blockage as the filter had not been changed in more then 150,000 miles. Any hoot check it for fuel in the vac line and also pull a fuel pressure test at the fuel rail and see what you have as low pressure will make it act like its starving and flooding will make it stumble and not want to run also when trying from a cold start. Even with new parts the new parts can fail or even be bad from the get go at times, this is why we always check thermostats before installing them. Good luck and let us know what you find on that FPR (Fuel pressure regulator)

 

[raceace73]

Alright so after changing a ton of stuff I borrowed the computer out of my brothers ranger and now mine seems to be running alright. I need to get one of my own and I was wondering what the best is?

Can I gain any fuel mileage in my OBD1 94?

Would using a OBD2 computer do me any good or harm?

Is it possible to use a OBD2 computer (ohv?)


More power and better mileage would be awesome but I do not know the limitations of the OBD1 computer.

Any help is appriciated.

Thanks,

 

[Roadrunner777]

More mileage, the first gen exp is good for about 18 mpg. Getting better mileage is a very popular subject, but if you are thinking of 20 or better, it just isn't there. You can open up the intake and exhaust, you will gain something there, you you need to do the math and figure out if the cost of parts and labor are worth it.

And, no, sorry, you cannot use the newer engine computer on a first gen exp. Completely different.

In my opinion, the downfaults of the first gen explorer are mileage and the automatic transmission, which if abused, fails. On the other hand, it is a very capable 4x4 with classic styling, and good off road potential.

It is what it is. Good luck, friend.