Ignition, fuel, maybe air? SERIOUS PROBLEMS PLEASE HELP

[sjohnson1699]

I have a 92 ford X with the 4.0L 4x4 with a 5 speed. I bought it two weeks ago and it ran great for the first day. Once it heated up I experienced it choking as if it was out of fuel. I pulled over at an Auto Parts store and switched the fuel filter. This got me home but did not solve the problem. Next I tried the coil, plugs, and wires. It seemed to run better but it could have been due to the engine cooling off. Once I realized it wasn't the coil I cleaned the MAF... This made it worse so I figured I had damaged the MAF and I replaced it. This is where I am stuck. I have fuel pressure and I know the pump is working (although I haven't done an official pressure test just a redneck version.) A friend tells me it's an ignition advancement problem he recommended either the crankshaft placement censor or flash the ECU. I am currently out of a vehicle and have the money to fix it but I am thoroughly annoyed with purchasing new parts that aren't turning out to be bad.... PLEASE somebody help.....

 

[awood]

Through the process of elimination, you'll figure it out. With each step, you need to make absolutely sure that everything is good before moving to the next step. You might fix it by throwing parts at it, but testing for, and replacing the bad part is way less expensive.

From what you've said, I would start with fuel pressure. Just because you have "pressure" at the test port, or somewhere else in the system doesn't mean it's good. If you have anything less than 30 psi (double check your specs) there will be problems. If there is say, 20 psi, you will never get the Ex to even start. You can "rent" a tester from some auto parts stores, then return for full refund. There are lots of posts here on the forum about fuel pressure. It's probably the most common issue. You can also have a problem with the fuel pump relay (along with the pump) as it heats up.

Do you have a Check Engine light? If so, search the codes on the forum here, and follow them through.

Good luck and don't give up!

 

[sjohnson1699]

Thanks for the reply!

I do not have a check engine light on. I replaced the fuel pump relay as well, and forgot to add that in. When I realized that wasn't the problem I returned it. I will test the fuel pressure and if its low is it undoubtedly the fuel pump? From my experience either a fuel pump works or does not work. However my experience level is not significant by any means.

 

[awood]

Something else to try. (I've never done this but I've read about it here).

See if it runs better with the MAF unplugged.

http://www.explorerforum.com/forums/showthread.php?t=263750