Need some electrical help with 94 YJ

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wminmi

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Jul 25, 2024
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South Haven, MI
i picked up a 94 yj (2.5, 5-speed) as a roller/project. Bought a running 2.5, 5-speed, t-case (heard it run before i bought it) and over the course of maybe 6-months or so finally got it installed.

While connecting all the wiring, i found some connections on the engine were different, so I bought new 94 sensors, etc and installed them.
Everything seems to be connected correctly.

All new relays under the hood, all new "max" fuses under the hood, all new fuses under the dash....

when i turn the key, normal pre-start warning lights come on, but turn the key to start and nothing happens, no click no nothing....can't hear the fuel pump kick on either :(
If i turn the key to run position, squirt gas in throttle body and cross the starter it fires right up and runs as long as i keep pouring gas in the TB.

I have replaced the ignition switch with a brand new one thinking that maybe the culprit, as well as cleaned all ground connections. Clutch slave seems to be full and working correctly (may need re-bled) thinking maybe a clutch/neutral safety switch and tried a few other little things. I'm out of ideas :(

Can anybody think of anything i maybe over looking? Engine runs GREAT when i cross the starter and keep gas in the TB.....no smoke, ticks, knocks, anything.....just can't figure out why no power to starter or fuel pump :(

Any ideas/input GREATLY appreciated!
 
welcome to forum. have you checked your codes? maybe be a bad battery cable to starter. what does your fuel pressure gauge read? are you getting a buzz sound from fuel tank?
 
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I have a 4.0 and not sure how similar they are, but maybe try jumping the relay for the fuel pump to check if it functions? If the pump doesn't work you might have to drop the tank and check the pump itself and it's connections.

I don't think the 94 YJ has a clutch safety switch.

Not sure if yours is accessible without dropping the tank but you could check the connector where the fuel pump plugs into the harness and test that power and ground are coming through. If it's similar there should be 3 wires and the two outside wires are ground and power (the middle wire is for the sending unit for the fuel gauge). Just be mindful that the power will only activate for a second or two while the fuel pump pressurizes the system, so you might need a friend to turn the key while you check for power.
 
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skyzero said:
I have a 4.0 and not sure how similar they are, but maybe try jumping the relay for the fuel pump to check if it functions? If the pump doesn't work you might have to drop the tank and check the pump itself and it's connections.

I don't think the 94 YJ has a clutch safety switch.

Not sure if yours is accessible without dropping the tank but you could check the connector where the fuel pump plugs into the harness and test that power and ground are coming through. If it's similar there should be 3 wires and the two outside wires are ground and power (the middle wire is for the sending unit for the fuel gauge). Just be mindful that the power will only activate for a second or two while the fuel pump pressurizes the system, so you might need a friend to turn the key while you check for power.
Click to expand...

I'm starting to dig through the wiring now. hopefully it's something simple. i can hope anyway ;)
 
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