and your talking about fuel pump relay 85 right?

 

Yes.

 

I want to make sure with you guys... but my jeep does not have an ASD relay right?

I've read online that could be a problem also, but I have not read anything about renix engines having them... all I see is ( front to back, passenger fender) oxygen sensor relay, fuel pump relay, latch relay, and lastly the a.c. relay

 

In a way, the fuel pump relay is the closest thing we have to an ASD yes, no ASD relay. Your problem is most likely the wire to the fuel pump is grounded. You can verify that by unplugging the pump and seeing if it's still shorted.

 

well had some spare time, use the multimeter on ohms for the side 85, and it showed this...

 

i thought maybe the ECU was not enough ground for the relay so i connected a ground of the chassis to the relay, big mistake on my part. There is an orange wire that goes to the starter motor relay terminal that started to smoke... So i guess thats my bad....

On the lighter sides of things i did not set the jeep on fire, almost though...

I also wanted to make sure the new pump worked so i attached power and ground from the battery and you can here the pump working, but was weird... it did not pressurize the system.

 

Measuring from where to where?

And was the relay connected at the time?

 

Maybe I forgot to mention. 85 only grounds the relay for 2 seconds after you turn the ignition on, then again when it starts. Have someone turn the key on while you watch the meter. That's the only ground the relay has.

How did you get power to the pump. at it's plug? Maybe it's out of gas, or you have the lines reversed, if that is possible.

Please listen to advice from posters instead of doing random tests and randomly jumping things. Fruitless, dangerous, pointless.

 

i measured the ohms just like you said, using the multimeter i had the black lead in the negative terminal... the red lead i touched the 85, the relay was connected to its respective wires... Red in 30, yellow in 86, orange in 87, and orange w/ black strip in 85.

with the my wife in the jeep and turning the key nothing came up...

 

what power are you talking about???? this whole forum is about no pressure in the lines... i have replaced the starter motor relay, replace the ballast resistor, replaced the fuel pump, did cruisers tip on new grounding locations (at the fuel pump connector, at the firewall to the heat shield, and negative battery to frame), i have replaced (2) relays...

Once again... there is power in red (30), there is power in yellow (86) but only with the turn of the key, there is no power with orange (87), but there is power with orange w/ black strip (85)

With this information, i have no power to the pump.... so it has to be a wire prob;em somewhere

 

No, that's not the correct way to test the coil on a relay. You need to pull it out and test from 85 to 86. Those two terminals connect to the coil inside. IIRC it should measure about 80-85 ohms for that kind of relay. Do not test for resistance (ohms) while connected to power.

 

OK maybe we are getting somewhere. So 85 didn't ground for a couple secs then the key ignition was turned on. Normally you would test just the socket with the relay out. Maybe you should do that just to be double sure. I don't want you buying a replacement ECU if you don't need one.

I did that resistance test on my 85 last week and indeed it grounds for just a bit, as expected. Just now I went out and checked mine for power at 85, both ign on and off. None, as expected.

With the relay out, if your 85 is not grounding a sec with the key on, and also showing voltage, ether it's wire if fubar somewhere, or the ECU took a dump.

Note; In a gang of wires in the loom, if any wire in there shorts out it can cut right through it's insulation and the insulation of wires next to it, then make contact. Or even more fun, connect two other wires. Point is something like that could be energizing your wire to 85. I suppose you could unplug the ECU. If that kills the power you are seeing at 85 then the ECU is done. If 85 still has power, it's wire has made contact with something hot.

Back to last week. Now with your new ground, can you jump power to 87 and hear the pump? NOW that 30 has become hot, you could just jump across from there, except 87 is grounding and blowing fuses, right? Or has that changed? When you ran the pump, did you do it from the plug or the socket?

How many volts do you read from 85? Maybe jiggle wiring and see if whatever you are reading changes.

 

Note from DJ regarding Fuel Delivery Problem
Post #18 by OP Batman33165
Well nothing so far I noticed that the harness that has the four relays is pretty much melted or corroded. So I am kind of desperate now, I cut the wires that would go to the fuel pump relay socket; they are red, orange, yellow, and orange/black wire. I cut the tips, then put on heat shrink quick-disconnect terminals so I can plug each connector on to the relay separately and still nothing.

I have power going from the red and yellow wire which if I am reading the Haynes manual is red (always hot) and yellow is when the ignition is on.

Just a note regarding this modification: it was probable not necessary they could have been cleaned and if you were looking at the black coating on the underside of the relay sockets that is a water proofing coating that AMC used to protect the underside of the sockets.
---------------------------------
Post #115 by Batman33165
Quote:
Fuel Pump Relay:
Key off/on: 30 (red) = 11.92/11.75, 86 (yellow) = 0/11.22, 87 (orange) = 0/0, and 85 (orange/with black strip) = 0/11.24. This shows my ground is getting power; but 87(orange) no power on fuel pump side

I have a question regarding 87 Orange Numbers 0-0 and the 85 Orange with Black Stripe Numbers 0-11.25 with key on. These numbers are exactly backwards to what I expected to see. The 87 Orange Numbers I would have expected to be 0 key OFF and 11.25 with the key ON and the 85 Orange/Black wire numbers to be 0-0.

So I’m including a photo of the Fuel Pump Relay socket that I want you to copy to your phone or make a sketch of it on paper and take it out to your Jeep.

Then take your Fuel Pump Relay in your fingers and point the wires down, then line up terminal 30 Red with the photo 30 Red and look at the colors of the 85 and 86 wires.

I’m wondering if you reversed these two wires location on the relay by accident; because you can plug them on the relay terminals wherever because of the above mention modification.

Fuel Pump Relay Socket:

 

Did you try probing ground wire furthur up in harness. Could just be bad connection at its connector.

 

Excellent diagram DJ. Doubt he reversed 85-86 since 86 comes on with ign as it should. I had thought he said he had POWER at 85. CF server denies me access when I look back at earlier pages "Prefetching is not allowed due to the various privacy issues that arise" Very annoying.

Agreed with Freedgr, that wire from 85.....worst case though is he upgrades to the improved 89-90 ECU.

Wonder if socket 87 to the pump is still shorting.