Mechanics

WHAT SENDS POWER TO FUEL PUMP RELAY.

1995 Jeep Wrangler • 10,000 miles

Was told by garage that my wife's jeep needed a fuel pump. I installed new fuel pump and strainer. Changed fuel pump relay. Jeep still will not start. When relay energizes fuel pump comes on, jeep will start. Have to wait for relay to energize, about 15 minutes. Not sure what to look at next.
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Joe Patrick
December 31, 2011.



When you say wait 15 min do you mean with key on?


Tiny
Fixitmr
Dec 31, 2011.
Yes with key on


Tiny
Joe Patrick
Dec 31, 2011.
I beleive ASD relay sends power to everything so car will start.


Tiny
Fixitmr
Dec 31, 2011.
The ASD relay is grounded by the PCM.


Tiny
Fixitmr
Dec 31, 2011.
Thank you very much, will try tomorrow


Tiny
Joe Patrick
Dec 31, 2011.
I have the same problem replaced fuel pump and both fuel pump relay and ASD relay still problem exists. What next?


Tiny
Gunny9129
Jan 4, 2012.
WITHOUT BETTER INFO

I PULLED UP "WRANGLER S" W/ 4.0L

2 DIAGRAMS--ENGINE PERFORMANCE CIRCUITS

FUEL PUMP IS ON THE 1ST--FAR RIGHT

I CAN READ 'EM GOOD IN MY DOWNLOAD---DON'T KNOW HOW GOOD ON 2CAR TILL I POST 'EM

LET ME KNOW IF I NEED TO FIND A DIFFERENT DIAGRAM (GIVE BETTER JEEP INFO) OR IF YOU CAN'T READ 'EM.I'LL SQUARE YOU AWAY

THE MEDIC


Tiny
CJ MEDEVAC
Jan 4, 2012.
The ECU runs everything, sends power to relays.I was looking at the ECU, used hair drier on it and jeep started right up. Let set for a while in cold and no start. Set up so I could start in mornings, but as I went down road cold air on ECU shut eveything down. Had to order new ECU.


Tiny
Joe Patrick
Jan 4, 2012.
Have heard alot of ecu replacements but never herd heat up made it work! Wonder how hard to disassemble and look for maybe obvious problem would be?


Tiny
Fixitmr
Jan 7, 2012.
I'm having a similar problem with my 95 Jeep Wrangler except cold air going down the road doesn't shut the ecu down. When you turn the key into the on position the seat belt light comes on like normal with the buzzing sound and then shuts off but the relays have no power until after 5-15 mins of sitting waiting and then the fuel pump relay and the auto shutdown relay start clicking building speed to a rapid click. After they stop clicking the fuel pump will turn on, car able to be started and runs fine. Could this be my problem? It sounds very similar to what I'm experiencing. The colder it is outside the longer it takes for the cycle to begin but like I said the cold air doesn't affect it after the vehicle has been running. I have checked all fuses and relays trying to figure out the problem as well as I have checked the wiring and everything is in order besides the dash illumination wiring and the windshield wiper wiring have been clipped by a previous owner and rewired to a switch for some reason.


Tiny
Perry89
Mar 24, 2012.
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