XanderXJ

So I bought a 1989 Jeep Cherokee 4.0L 2wd that is being converted to a 4wd a couple months ago and it ran and drove when I bought it but as soon as I got it home and off the trailer it would die giving it gas. The fuel pump had a high and constant whine to it so I replaced it and it started up a few times and ran but would die and not start back without a brake cleaner assist. Replaced the TPS, fuel filter, cleaned the tank, relays are good, replaced the fuel pressure regulator, replaced the fuel pump again bc I thought maybe it died and tested it outside of the tank to make sure it worked. It worked but I can't hear it turn on inside the tank. (yes it has gas in the tank). Hooked a fuel pressure gauge to the port on the fuel rail and it reads zero. None comes out when pressed either. So I'm stumped and have no idea why it wouldn't start or not getting fuel. Maybe a bad PCM?

tech

Have you checked to see if the fuel pump is getting power and running when you crank it ?

XanderXJ

It was when I tested it outside of the tank before reinstalling it. Put it in a bucket of water and turned the key and it was pumping.

awg

others may comment, but if you are saying you ran water thru an FI fuel pump, I would consider it to be junked

XanderXJ

I've seen people do that before to test them and they were fine but who knows.

cruiser54

Go to www.cruiser54.com and complete tips 1 and 2 before anything else.

lawsoncl

And 29 for the fuel pump ground. See if you have voltage at the fuel pump ballast resistor. It can be bypassed altogether if it's broken.

Lordmonk3y

You never said whether or not you changed the fuel filter. Could be completely clogged. I agree with double checking making sure your pump is working (although I probably wouldn't have used water) but if it is go downstream and check the next stops.

Pressure test before and after the filter by taking it out of the line temporarily to test with just a little coupler in its place. Then test with it back inline. Ideally your filter should not drastically change your fuel pressure. If it is, replace it. (might be good to do anyway as it's not like they're expensive)

doublechaz

Here is a crazy theory. In all that parts cannon, did you get the return line and supply line crossed at the pump?