I learned THE HARD WAY, that a noisy fuel pump on your XJ should be inspected. I have a 91 that gave me an EXTREMELY hard time trying to figure out why I had no power under load. I replaced the TPS, MAP sensor, O2 sensor, CAT, fuel pressure regulator, cleaned the valve cover (L6), cleaned the CCV system, etc. The whole time the fuel pump had a really loud whine, when I was finally out of ideas to try I went to the fuel pump, and what I found was the strainer or 'sock" on the inlet of the pump had rotted and clogged up the inlet port. Once I cleaned it, the pump stopped the noise and the engine seemed to come back to life. I had power all of a sudden......Save yourself the trouble and check your fuel pump if you have this issue.

 

Good [if not obvious] advice.

 

Just would like to save people with this issue the time, money, and stress this caused me. I was almost ready to sell her it was driving me so crazy!

 

That's why we suggest fuel pressure tests right off the bat in the diagnostic process. Otherwise a guy can get off on a tangent replacing expensive sensors.

Seems that alot of people are running their Jeeps real low on gas before refueling, causing the pumps to suck up crap off the bottom of a 25 year old metal fuel tank, too.

 

I did fuel pressure test multiple times and a compression test, all with good results. And I was one of those guys that went off on a tangent replacing **** man it drove me crazy!

 

So the fuel pump passed the test initially?

 

Yes it did. So always be weary of the fuel pump if you can't figure out why your Jeep "won't go". Damn drove me nuts for months!

 

Might be a good idea to drive the Jeep with teh pressure tester attached and the gauge under the driver's wiper.....

 

Thought about installing one at one point lol