1988 xj starts then quits
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
OK. It seems there are two separate wires that are energized when you turn on the ignition. One red, and one "YL". I might get under the dash with a meter and a paperclip or a needle or something and see that "YL" is getting power when the key is on. I would check the red as well.
But First!!. Do a number on that C-101 connector and see if that clears it up.
But First!!. Do a number on that C-101 connector and see if that clears it up.
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
Got 15 inches and "ctrl" + "+"......no directory on my bootleg FSM's! 
I get lost in 100's of pages of "other"......I do get a little steamed up, they did not make it easy. 
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
CF Veteran
Joined: Aug 2011
Posts: 10,489
Likes: 24
From: Nor-Cal Coast
Year: 90,84
Model: Cherokee
Engine: 4.0,2.5
use this it has a directory.....http://jeep.zerok.ru/index.php?page=XJ
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Hey! Progress at least. (it will do a beer run now)
I believe it get's power from the pump relay, (third one back), only when the ECU grounds it to activate it.
Idk if the relay get's power from a fusible link or the ign switch...(the air is so thin up at Cruisers, he's probably taking a nap)
Just curious, wonder if it runs with that relay pulled. Might be inlightning.
I'll see if I can read some diagrams, (in the PDF muck), I'd like to know that myself......
EDIT< Ah! ^ Cool Freedgr
I believe it get's power from the pump relay, (third one back), only when the ECU grounds it to activate it.
Idk if the relay get's power from a fusible link or the ign switch...(the air is so thin up at Cruisers, he's probably taking a nap)
Just curious, wonder if it runs with that relay pulled. Might be inlightning.
I'll see if I can read some diagrams, (in the PDF muck), I'd like to know that myself......
EDIT< Ah! ^ Cool Freedgr
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Thread Starter
Newbie
Joined: Mar 2012
Posts: 18
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From: south thomaston maine
Year: 1988
Model: Wagoneer
Engine: 4.0
So if everything is fuctioning properly should the fuel pump run continuously if the key is on, or should it cycle on and off as needed to maintain pressure?
CF Veteran
Joined: Mar 2010
Posts: 47,923
Likes: 38
From: Broward County Fl.
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
CF Veteran
Joined: Nov 2011
Posts: 1,290
Likes: 0
From: phoenix az
Year: 1989
Model: Cherokee
Engine: 4.0l 6 cylinder
Originally Posted by hellrazor
So if everything is fuctioning properly should the fuel pump run continuously if the key is on, or should it cycle on and off as needed to maintain pressure?
anyone know y