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View Full Version : pain in the arse.......stumped


xj-jamie
12-28-2009, 09:30 PM
So i thought i could make it that little bit longer driving on the E i ran out of gas......

got the truck towed back to town after putting gas into it and still getting no turnover...

the symptoms : the truck turns over and does start(also at crank pulls 39 psi on the tester) but quickly drops to near nothing sputters and dies...

when i changed the fuel pump as that was thought to be the initial problem i discovered that the fuel tank had taken some rough hits resulting in dents in the tank that had knocked the old sock off the pump intake. socafter banging the dents out i was back in business and chasing the elusive problem...


after testing the relay and wiring for the relay it was getting its inital signal and pulling 39 psi but after the two seconds the voltages drops and the truck dies... the relay is working....

whatever is supposed to keep the signal going and keep the pump working just stops??

there does appear to be the remnants of an alarm system maybe that is interfering and cutting the flow??

we just took the relay out and jumped it so it drives and works but its not proper...


any ideas??? kinda stumped at this point this only happened after running it out of gas...

tchevy
12-28-2009, 09:51 PM
if the pump is only doing a 2 second prime and shuts off during crank it didnt happen from running out of gas. just a coincidece. ignition switch could have failed among other things.

Happypants
12-28-2009, 09:51 PM
If there are reminants of a alarm, long shot but there could be a electric kill switch that had been triggered? Prolly not but you never know, a common problem on the pre 91 xjs is the wiring for the pump fucks up and dosent keep the signal through the relay thus starting the dying, if you jumped it to keep it running you can leave it but you may run into a leaky injector cause essentially your supposed to be running at 30 psi, not 39 psi cause you will be running constantly on the psi that the pump primes at and starts the truck at, if you can pm tony (dh_4_ever) he may be able to shed more light on this for you as he had the exact problem you did, hope this helps
Nick.

Nutbar
12-28-2009, 10:18 PM
Check the fuel pump ballast resistor, it is a common failure on the Renix XJs. The ballast resistor is a white ceramic block about 3 in long beside the air filter box on the drivers side fender well. Pull the 2 wires off of it, they are orange with a black tracer on an 89 IIRC, and jumper them together see if the truck stays running.

xj-jamie
12-29-2009, 09:49 AM
So pull the two wires jump them, start the truck. if it runs?? and what if it doesnt im heading to tge shop soon ill let u know


i dont think its anything to do with old alarm either nick thatll be last effort i guess


thanks guys i will report bacK

Lazybaka
12-29-2009, 10:42 AM
no codes ?

bcmaxx
12-29-2009, 11:52 AM
no codes ?

Too old for codes, back to the basics troubleshooting on these damn things (kinda like the atari of fuel injection systems)

Lazybaka
12-29-2009, 12:01 PM
sorry didn't see the age of the truck :)

bcmaxx
12-30-2009, 10:22 AM
Any luck sir?

So pull the two wires jump them, start the truck. if it runs?? and what if it doesnt im heading to tge shop soon ill let u know


i dont think its anything to do with old alarm either nick thatll be last effort i guess


thanks guys i will report bacK

xj-jamie
12-30-2009, 10:45 AM
i didnt think about it when i read it but if i pulled the wires off of the ballast the whole truck should just die and isnt really relevant to the problem.

the relay port itself has power coming through to the ground side of the relay, so itssomething to do with the relay wiring itself and whatever delivers the signal and keeps it coming.


as of right now i am at a stand still and just using the jumper wire


i just spent the last two days doing work to the jeep.... i need a little break........ i am just doing to some net research on the issue

bcmaxx
12-30-2009, 10:49 AM
i didnt think about it when i read it but if i pulled the wires off of the ballast the whole truck should just die and isnt really relevant to the problem.

the relay port itself has power coming through to the ground side of the relay, so itssomething to do with the relay wiring itself and whatever delivers the signal and keeps it coming.




as of right now i am at a stand still and just using the jumper wire


i just spent the last two days doing work to the jeep.... i need a little break........ i am just doing to some net research on the issue

Sucks man, If you can weed through the b.s. Naxja is fairly resourseful, just tell their "search nazis" to fuck off and die

Little Samurai
12-30-2009, 10:51 AM
Could be the relay is pooched? Try and locate the relay for your Daytime running lights and see if it is the same, if it is put it onto the fuel pump wiring harness and see if it works. Sometimes they just get corroded and old and don't hold in that well anymore.

xj-jamie
12-30-2009, 03:34 PM
We did test the old relay and it worked fine as well as switched in another and still had the same issue

dh_4_ever
01-04-2010, 05:18 PM
I had the same problem in my 89.. where abouts you located? I could come take a look at it.. you check the fusable link?

renix engines have two fuel pump curcits, the run mode and start mode. will it still run if you hold it in start?

xj-jamie
01-04-2010, 09:19 PM
I had the same problem in my 89.. where abouts you located? I could come take a look at it.. you check the fusable link?

renix engines have two fuel pump curcits, the run mode and start mode. will it still run if you hold it in start?

Ridge pm sent thanks

Tinker
01-05-2010, 05:42 AM
Gremlins I blame the Gremlins. Mischievious lil fawkers they are very prominent in those OllllO things. It happens from parking to close to a ford I do believe:D

xj-jamie
01-05-2010, 10:54 AM
Gremlins I blame the Gremlins. Mischievious lil fawkers they are very prominent in those OllllO things. It happens from parking to close to a ford I do believe:D

HAHAHAHA i am always wheeling with a ford haha musta jumped over

Lazybaka
01-05-2010, 12:01 PM
*nod* hella yeah !