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fuel problems

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Old Nov 13, 2013 | 10:50 PM
  #1  
Nicolai's Avatar
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From: Puerto Rico
Year: 1988
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Engine: 4.0 L (242 CID) AMC 242 I6
Default fuel problems

I got two problems whit fuel.on my 87 xj
1) my fuel pump stop working a few month ago when I crank my jeep it just stop pumping. Now when I feed it directly to a accessory the pump works. But she won't mark a full tank just empty. The white wire It's wats keep my fuel pump on. Relays are fine

2).I'm getting a strong fuel smell I just dont know what to do. I was told replace the fuel injectors.
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Old Nov 13, 2013 | 11:35 PM
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On the inner fender by the air cleaner is a ceramic resistor with orange wires. Check it's connections or just bypass it. Power out the rear of that goes straight to the pump.

Also;
There is a brittle little tube. It comes out of a rubber plug, low on the engine side of the throttle body. It runs back to the firewall, then up to your MAP sensor sort of high up there near center on the firewall. CRUCIAL!! The MAP will tell the ECU to dump fuel with less/no vacuum. Any crack or blockage and it will be pig-rich. (black smoke, fouled black plugs). You can pull the line off the MAP and feel for vacuum with your finger. If it runs!


ALSO Take a really good look at your injectors. The originals are known to leak where the housings come together.


Check out Cruisers stuff found in my signature. Bunch of great stuff there
on your Jeep!
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Old Nov 14, 2013 | 06:08 AM
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Here's a photo of the fuel pump ballast resistor.
Attached Thumbnails fuel problems-ballast-resistor.jpg  
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Old Nov 14, 2013 | 04:49 PM
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Weird my ballast has three cable not two
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Old Nov 14, 2013 | 05:29 PM
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Originally Posted by Nicolai
Weird my ballast has three cable not two
Post up a pic.
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Old Nov 15, 2013 | 08:59 PM
  #6  
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Here it is

fuel problems-forumrunner_20131115_225845.jpg
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Old Nov 15, 2013 | 09:21 PM
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That's really odd. Are the connectors good and tight?
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Old Nov 16, 2013 | 01:10 AM
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If that is an 88, and that's on the inner fender near the air cleaner, connect the wires together and throw it towards who ever put it there! (but save it )

Besides sending messages to Alien Invaders, all it does is knock the voltage to the pump down a bit to make it less noisy. Just my .02 anyway.
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Old Nov 16, 2013 | 01:13 AM
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Bar codes in 88?
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Old Nov 16, 2013 | 09:59 AM
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Year model 87
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Old Nov 16, 2013 | 07:08 PM
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Oh heck, I didn't have the right glasses! (I thought the whole white rectangle was your ..thing).

Yea, likely there are two on the powered side because it can be powered by different circuits. Ours are likely the same, just the wires connect before the resistor.

I think you should see system voltage, 12 to 14, on the powered end, and a few less out the other to the pump. Me, if I had any question I''d just pull the wire to the pump off, and jump it to positive to test it.
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Old Nov 16, 2013 | 11:33 PM
  #12  
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Thats what I did I jump it. But when I did. It's stop making my fuel
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Old Nov 17, 2013 | 04:38 PM
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You are going to need a meter to deal with that 88. If the pump won't run/no fuel, checking voltage there at that resistor is something I would want to do.

Even the $5 Harbor Freight meter actually works. For a while anyway.
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Old Nov 20, 2013 | 01:54 PM
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I got it fix. New ballast and relay. New fuel pump. Now I wanna upgrade my fuel injectors. I heard . From srt4 Neon to 5.0 Mustang what about BMW
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Old Nov 20, 2013 | 08:03 PM
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Glad you got it fixed!
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