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Discussion Starter · #1 ·
Hi,
Just replaced fuel pump and no fuel pressure. Pulled the line in front of the tank and nothing. does somebody have a list of fuese and relays to check please. Thus far, I'm not seeing anything under the hood that's bad (fuse wise). Other thoughts

thanks,

89 trooper
5speed 4 cylinder
 

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The pump relay should be labeled via the clear cover atop the fuse box. Many times the wire gets corroded / broken / etc at the male / female connectors located immediately in front of the tank, passenger side. Sometimes, though not often, you can disconnect the two, spray some wd-40 in them and reconnect and it works. Other times (more often), it will be the hot wire going to the pump (at the connectors). Believe it's a red wire. You can also pull the a/c relay and swap it with the fuel pump relay to see if it's relay related or another issue (wire).
 

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Check the charge relay, too.
 

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Discussion Starter · #4 ·
what's the charge relay?
Also, swapped relays, checked wires and still not running?Time to call a mobile mechanic??
 

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You sure it's not the alternator? Have you done the jumper test? It's been written up here many times.
 

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Discussion Starter · #6 ·
Hi,
I don't understand how the alternator would stop the flow of fuel from the tank? I disconnected the fuel filter and when I crank it, there is no fuel flow????????
 

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If it's similar to the Amigo, after the engine starts, the fuel pump is powered through the contacts of the fuel pump relay, which is energized through the contacts of the charge relay, which is only energized if the alternator is working. During cranking though, it's powered through a fuse in the dash fuse box from the "hot-in-start" circuit.
 

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I have written about this many times. Do yourself a favor and search for it. Lot less work than replacing parts that don't need replaced.
 

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Discussion Starter · #9 ·
Hi Squatch,
Would you be so kind to send me the link to the article please. I've searched via alternator, fuel and your monikor and find much info, but few specifics.

thanks,
paul
 

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Discussion Starter · #11 ·
So, I bypassed the fuel relay with a jumper and hear no noise at the tank from the fuel pump. does this mean the wiring to the pump is bad (or heaven forbid, I installed a defective pump)??
thanks,
 

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ohanahorse said:
So, I bypassed the fuel relay with a jumper and hear no noise at the tank from the fuel pump. does this mean the wiring to the pump is bad (or heaven forbid, I installed a defective pump)??
thanks,
Sounds like one or the other. Cut to the chase. Run a length of wire from the POS battery post to the pump hot wire AFTER the connector located in front of the tank passenger side. That will bypass the circuit up to the test point and then you'll know if it's the pump or its circuit.
 
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