Won't fire ?
06-13-2011, 11:30 PM
#16
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Year: 1990
Model: Cherokee
Engine: 4.0
onother place to put the test light is unplugging the fuel pump plug underneath. the middle wire in the 3 wires is for the pump power. i think it is pink with black stripe. one of the outside wires is power for the sending unit and it will have constant power with the key on. the third is the ground.
06-14-2011, 11:05 PM
#18
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Well, I couldn't find my test light and just as well as the volt meter gave me this reading at the fuel pump plug 7.22. Sound ok? I can hear the pump coming on for a couple of seconds. Which I presume it's going off because it builds pressure and has a pressure sensor switch.
I then tried swapping all of the relays and no luck. So I started at the coil wire. It's putting out a weak yellow spark to ground, but when held next to the dist cap terminal - nothing. At all. So my questions is:
Is the electronic ignition causing me not to see a spark to the cap coil tower?
Or what. How can I see a spark to ground everywhere but the center terminal on the cap?
It won't start. Even with ether.
I then tried swapping all of the relays and no luck. So I started at the coil wire. It's putting out a weak yellow spark to ground, but when held next to the dist cap terminal - nothing. At all. So my questions is:
Is the electronic ignition causing me not to see a spark to the cap coil tower?
Or what. How can I see a spark to ground everywhere but the center terminal on the cap?
It won't start. Even with ether.
Last edited by RebelRed; 06-14-2011 at 11:07 PM.
06-16-2011, 07:08 PM
#20
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Model: Cherokee
please help
Here's what I found - plus there's no ballast resistor on this one.
I couldn't find my test light and just as well as the volt meter gave me this reading at the fuel pump plug 7.22. Sound ok? I can hear the pump coming on for a couple of seconds. Which I presume it's going off because it builds pressure and has a pressure sensor switch.
I then tried swapping all of the relays and no luck. So I started at the coil wire. It's putting out a weak yellow spark to ground, but when held next to the dist cap terminal - nothing. At all. So my questions is:
Is the electronic ignition causing me not to see a spark to the cap coil tower?
Or what. How can I see a spark to ground everywhere but the center terminal on the cap?
I couldn't find my test light and just as well as the volt meter gave me this reading at the fuel pump plug 7.22. Sound ok? I can hear the pump coming on for a couple of seconds. Which I presume it's going off because it builds pressure and has a pressure sensor switch.
I then tried swapping all of the relays and no luck. So I started at the coil wire. It's putting out a weak yellow spark to ground, but when held next to the dist cap terminal - nothing. At all. So my questions is:
Is the electronic ignition causing me not to see a spark to the cap coil tower?
Or what. How can I see a spark to ground everywhere but the center terminal on the cap?
06-16-2011, 09:59 PM
#21
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Model: Cherokee
the 90 has a resistor on the drivers inner fender. tan ceramic looking...about 1 inch wide and about 4 inches long. two orange wire with black stripe. you can test for 12 volts there fairly easily. there should be power for 3 sec. when the key is first turned on then shut off. then there should be 12 volts there when the key is in the crank position. the resistor can be bypassed and even eliminated completely if it is bad. the relay is on the passenger sidefenderwell. it may have a flat plastic cover over the relay bank. there are 4 identical relays there the fuel relay is the second from the front. you can switch it with the others to test it
06-16-2011, 10:23 PM
#22
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08-13-2011, 04:15 PM
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I've tried two other jeep sites and no one can help. Two days ago I put another new pump in, and it doesn't work either. I've swapped relays around to no avail.
I can't find where the ground wire from the three wires that go to the pump go, so I can't check for ground. Yet.
I tried using a paper clip to jump across the relay contacts. Nothing.
Anyone? It's going on three months and still no fuel pump.
$100 bucks to the first person who figures it out.
909-844-1081
Bruce
I can't find where the ground wire from the three wires that go to the pump go, so I can't check for ground. Yet.
I tried using a paper clip to jump across the relay contacts. Nothing.
Anyone? It's going on three months and still no fuel pump.
$100 bucks to the first person who figures it out.
909-844-1081
Bruce
08-13-2011, 04:21 PM
#25
Originally Posted by RebelRed
I've tried two other jeep sites and no one can help. Two days ago I put another new pump in, and it doesn't work either. I've swapped relays around to no avail.
I can't find where the ground wire from the three wires that go to the pump go, so I can't check for ground. Yet.
I tried using a paper clip to jump across the relay contacts. Nothing.
Anyone? It's going on three months and still no fuel pump.
$100 bucks to the first person who figures it out.
909-844-1081
Bruce
I can't find where the ground wire from the three wires that go to the pump go, so I can't check for ground. Yet.
I tried using a paper clip to jump across the relay contacts. Nothing.
Anyone? It's going on three months and still no fuel pump.
$100 bucks to the first person who figures it out.
909-844-1081
Bruce
08-13-2011, 04:46 PM
#26
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Year: 1997
Model: Cherokee
Engine: 4.0 Liter
Check the emergency fuel pump relay located on the right kick panel. It cuts power to the fuel pump. You can reset it yourself.
Flash
Flash
08-13-2011, 04:49 PM
#28
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The crank position sensor would stop 12 volts from going to the fuel pump?
Let me recap. I have no fuel pressure. The pump does not run. The first new pump I put on 2 months ago ran for 5 seconds, which I figured was ok as it probably shut off after pressure built, right? But back then I had a second problem of a bad coil. The coil is fixed. It starts with ether. I need fuel...
Let me recap. I have no fuel pressure. The pump does not run. The first new pump I put on 2 months ago ran for 5 seconds, which I figured was ok as it probably shut off after pressure built, right? But back then I had a second problem of a bad coil. The coil is fixed. It starts with ether. I need fuel...
08-13-2011, 05:40 PM
#29
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"Emergency fuel pump relay" really. Sounds redundant.
Right kick panel, meaning passenger side?
Looked - Nothing there. Well, if it was a joke you got me to look. If it's for real it's not located there.
Right kick panel, meaning passenger side?
Looked - Nothing there. Well, if it was a joke you got me to look. If it's for real it's not located there.
08-13-2011, 05:47 PM
#30
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Model: Cherokee