PDA

View Full Version : YJ fuel pump problem.


Buck Master
02-27-2006, 04:40 PM
Usually when you turn the key to just before it cranks over you can here the fuel pump purge. I don't here this anymore and as a result it won't start. Its happened before so I changed the pump and everything was good for two months. Back to the same thing now. Anyone run accross this before? Is it the pump or elecrical? What do i check for before I yank it out again?

Princess
02-27-2006, 04:52 PM
its a jeep thing dude.... i had the same problems at one time and it was dirty lines, shitty carb and bad fuel pump.... stupid lucy [27]

stuckle
02-27-2006, 05:01 PM
Usually when you turn the key to just before it cranks over you can here the fuel pump purge. I don't here this anymore and as a result it won't start. Its happened before so I changed the pump and everything was good for two months. Back to the same thing now. Anyone run accross this before? Is it the pump or elecrical? What do i check for before I yank it out again?

there should be a seperate circuit for the fuel pump purge i belive. On the chevy's theres a connecttion you can jump to check the pump....

re0check your relay...and check to see if you can find any info on a seperate purge circuit...cause that might be the problem...

other than that i dont know...did the computer regester a fult for low fuel pressure before it stopped working?

is it carb'd? soak your air filter in gas....see if it will run and then if the fuel pump will kick in?

Buck Master
02-27-2006, 05:04 PM
No fault registed. I also swapped relays and that didn't do anything. I am thinking that it might simply be the pump again.

stuckle
02-27-2006, 05:11 PM
No fault registed. I also swapped relays and that didn't do anything. I am thinking that it might simply be the pump again.

that would be surpisingly quick...

is the fuel pump inline or in tank? if its inline.....check your fuel filter and probably replace it...could be clogged or letting junk pass into your pump...

if its intank...a few tips....fill up at gas stations used alot, and with newer tanks. I like to stick to shell, chevron, or esso. Also, try not to let your tank run below 1/4 tank...tends to let all the shit that has settled to the bottom of your tank get stirred up and sucked up...

fourplay
02-27-2006, 09:11 PM
mechanical pump, have a spare if ya need it..
[cheers] Jim

Nutbar
02-27-2006, 09:46 PM
what year and what engine for your yj

Buck Master
02-28-2006, 01:21 PM
Its a 1990 with a 2.5L

Nutbar
02-28-2006, 01:30 PM
I have run into ECM problems on the 87 - 90 tbi 4 bangers but rarely check relays for fuel pump and power latch relay and the other one I have found is check your conections through the sending unit in the tank also it would not be the first time I have had trouble with brand new aftermarket fuel pumps on my third warranty carter one in my cj with fuel inj

Buck Master
02-28-2006, 04:32 PM
It looks like I have no choice but to yank out thefuel tank...again.

Nutbar
02-28-2006, 04:35 PM
Have you at least put a test light on the fuel pump power wire and had someone cycle the key
it should be a 3 wire plug from the tank and the fuel pump power should be an orange wire.

Buck Master
03-01-2006, 11:20 AM
I'll try that first. Should it have power all the time or just for a second when it should prime the system?

Nutbar
03-01-2006, 12:41 PM
It should get momentary power for about 10 or 15 seconds when you turn the key on.

Buck Master
03-01-2006, 01:17 PM
Just curiuos. Once it primes and starts up, what happens after that. Does it give the pump power only when it is low on pressure. How does it work?

Nutbar
03-01-2006, 01:21 PM
when you turn the key on the ecm primes the pump one cycle then when you start cranking the ecm turns on the fuel pump and the power latch relay keeps it on until there is no more signal from the TDC sensor (crank sensor on the flywheel).

Buck Master
03-14-2006, 03:26 PM
OK. Tested to make sure there was power to the pump and there was. So i figured it must be the pump. Pulled it out and put a new one in. Did the same thing. Anyways to make a long story short, it was the ground wire. It was fine from the pump so when I checked it with the test light all appeared fine. Reground it and all is good now.

Does any one new an almost new fuel pump for their YJ. I have a spare.