89XJ801

I'm new to the forum and haven't joined one before. so i hope i get it right.

So today or last night i guess lol. i bought an 89 Cherokee limited. It has a fairly clean interior and a 3" lift.

One of the problems with it was that the fuel pump had gone out. not a hard fix. right? The previous owner put an inline fuel pump where the fuel filter is supposed to go, and then just hooked the inline pump onto a battery in the back of the jeep so that he could drive it. fired up first time when i test drove it.

I figured the jeep was worth the price even if i had to replace the fuel pump.

Drove the jeep home in that condition and went to the parts store for a new filter and pump.

changed out the old pump last night. (did it without dropping the tank, not going to do it that way again..) just got done at 5 am lol. went to try and start it and its doing the same thing, just cranking but wont fire.

i read in another post to check one of the relays on the passenger side of the engine compartment. but dont know which one it is. Haven't got a service manual yet because the 24 hour parts store didnt have one.

other than that i dont know what to check. can you give me anymore ideas?

Thanks in advance!

Desert Rat

Sounds to me like a fuel pump relay. If the relays bad then you wont have any power going to the pump. I checked my Haynes manual but it does'nt indicate which relays for the FP. Most auto parts stores will test relays for you for free, I'd try that. Welcome to the forum by the way, check out the Northern Utah BS thread, a bunch of us put local runs together from time to time.

clayton3854

really nice front bumper man, welcome to CF.

djritter1122

could also try switching the relay around till u fing the bad one? maybe?

found it

89XJ801

Thanks a lot guys! I'll try the relay today, hopefully that is the problem!

89XJ801

Thanks, im going to take it off and modify it a little. have hit my knees on the outside corner too many times already.

89XJ801

I replaced the relay today, its still doesn't want to start. It just cranks.

I touched the power line that goes to the pump with a test light and it looked like it was being short volted or something. is that power line supposed to be right at 12v? short volt would mean not enough pressure right?

I may hook a battery up to the power line and see if it will run.

Any other suggestions?


thanks again!

Desert Rat

Shot in the dark, does your fuel pump have a good solid ground?

89XJ801

I can hear the pump running back there.

Good question. I dont know. I will check that next.

If the fuel pressure was too low would the fpr not let any fuel into the rail?
maybe i will just have to go get a pressure gauge and see.

89Laredo

Check your ballast resistor.
An easy thing to do would be to disconnect the two wires running to it and jumper them together.
When the key is turned to "on" battery voltage is sent straight to the pump for 3 seconds. When the key is turned to "run" and the engine is running, voltage goes through this resistor.

89XJ801

Alright, have a couple things to check then.

ground and the ballast resistor.

Had to go back to logan for school so its sitting in my parents garage in west jordan. hopefully get it figured out friday

MrJCRod

If you here it running then check fuel pressure first. If there's no pressure and you hear the pump running then check for proper voltage at the pump when you first cycle the key. If that's there then something could be wrong with your install. You may have to drop the tank and pull the pump again to make sure everything is installed correctly. Did you pull the inline fuel pump off after you installed the new pump in the tank?

89XJ801

That would suck. Yeah I pulled the inline. they had just taken the fuel filter off and put the inline in its place. So i took it out and replaced it with a filter.

Thanks for the help! Wish i was able to work on it during the week. Dang college. lol

89XJ801

My Dad figured it out!! He got it started and running tonight.

turns out the previous owner had cut the power lines to the fuel pump and when he put them back together he got them backward? dunno how they are different colors lol

but now we have a running XJ!!

Zreiser

wow i hate idiot PO's! My XJ's all derp'd up because of my PO too. glad you got it sussed out though mate. Now i know what to stay on the look out for.