Sorry this post is a little long winded, but I wanted to make sure I covered everything in hopes that someone had some advice on where to start diagnosing my problem(s).

I just rescued a 1992 Ranger 4X4 with a 4.0 from a farm field. It had not ran in almost 3 years, although it was said to be in running order when parked. It only has 84,000 miles and by the records and condition, seems to have been well cared for and serviced regularly.

I immediately replaced plugs, pos battery cable, air filter (which had recently hosted a mouse), pcv, fuel filter, oil & filter, completely drained the gas tank and replaced the fuel pump & sending unit which were bad. After that, no spark but fuel was again flowing. After quite a bit of visual inspection and some basic diagnostic testing, I found that someone had cut the wires to the crank position sensor. I made a repair of the wires, and she fired right up! That's the good news...

The bad news is that when I took off for my inaugural flight, there is an extreme hesitation at about 2000 rpms that you just can't get past. It is almost like it shuts down at that point. If you let off the gas, it will allow you to get up to 2K again, and then down it goes...almost like the fuel just shuts off. I also noticed, and I'm pretty sure it's not my imagination, but when I go up a steep incline, it does the same thing, but at no particular rpm. Could this be a faulty Fuel Pressure Regulator? It almost seems like it is instantly running out of gas, no sputter...just nothing. The other things that I am aware of, but am not sure about being a contributing factor is that it throws an MAF code, and there is an obvious leak in the filler neck hose. Any ideas where to start?

Thanks!

Steve D

 

Well, fix that leak and check the MAF wiring and the MAF itself. Check the intake as well, air blockage could cause a loss of power, though it is odd that it occurs at 2K rpm or so, no matter what gear apparently. That would be a good place to start. And might wanna have a good reliable mechanic look over the whole thing for anything he/she notices that you didn't. Don't let them do the work, just check it out, should be quite a fun project and will treat you great as soon as we get everything cleared away.

 

Welcome to FTE!

Check the fuel pressure, that'll help you figure out if it's still a fuel delivery issue.

A bad MAF could also cause what you are experiencing.

 

Exactly what code(s) #(s) are you getting? Please make note if they are a KOEO, KOER, or a CM code. BTW, don't get too antsy on that MAF just yet. My former 94 threw a couple of MAF codes, the real problem that was triggering the MAF code was the IAC solenoid. There never was a MAF problem. Thank God for diagnostic flow charts . And yes, do check the fuel pressure to rule out a delivery problem.

 

The code it threw was 157 - "MAF sensor ciruit below minimum voltage".

Thanks!

Steve D

 

It turned out to be the MAF sensor. Thanks to everyone who responded to my two posts!

Steve D