epowers777

Ok i did a bunch of testing and then it started raining and I left the paperwork in the jeep!!

I got to the fuel pump plug. I unplugged it and tested the pump side of the harness. I have continuity on all three wires. I dont think that is normal?? pump grounding out??

Dave51

To be clear, you are measuring the pump?

If you're measuring the pump I think that the center pin on the connector to ground will be 0-88 ohms depending on how much gas you have, and bridging the two side pins should be 0-20 ohms. If it's like 2.0 ohms or less the pump is dead, and 15-20 ohms means it's fine ("fine" may vary depending on the pump manufacturer).

Perhaps somebody with a good pump lying around can confirm this.

Dave51

Or even better somebody with a bad pump lying around can confirm this.

Dave51

BTW did you inspect the harness? There appears to be a very vulnerable area where the pump harness enters the body (at least in the later models) that could be a spot where a short might occur.

epowers777

soooo replaced the pump with one in my parts jeep and it still does the same. I checked the wires under the seat but did not pull the wires thru the rubber to inspect. I will do that. I also checked the wires by the driver door brake pedal.

I had an extra ecu from my parts jeep and replaced it still didn't fix the problem.

I'll post number soon from the relay.

I tested the wire that starts the starter. With the relay in it drops the volts to 2 volts while attempting to start. With relay out there's 11v while attempting to start (cranks normal no fuel pump relay out)

epowers777

starter relay
battery feed from ignition switch 12.2v while cranking drops to 10v
battery feed from fuse link 11.7 cranking drops to 9.7
ground wire continuity check good .58 continuity
injector feed .035 continuity


Wire to starter to engage.
Relay in 2.4v
relay out engine cranking 9.8v

gat

What were your results when you shoved the multimeter's tips into the female ends for the fuel pump relay? Voltages, continuities between wires, continuities to ground, and continuities to power?
That information will help to find a short. An open should act the same with or without the relay connected.
If you post these, then I might just test my 1988. I, also, might have a good pump and bad pump in my parts in the shed.
I suggest starting at the wires that connect to the relay. Maybe you need to go toward the pump. Maybe you need to go the other direction.

epowers777

i messed up those number are for the fuel pump relay.

gat

Diagram of XJ Relay
Continuous to
# Volts Ground Power
30 12.4 X Y
85 0 Y N
86
87
87A
That might help us to determine where a short is present in the system. If 30 is continuous to both battery positive and battery negative terminals, then we have a problem that is in the other direction of the fuel pump - as an example.

Hopefully, we won't need a table of continuity between the individual connections. In case we do ...
30 85 86 87 87A
85 Y N N N
86 N Y
87 N Y
87A N Y et cetera

Dave51

Can you list your "continuity" values in ohms?

Can you test the resistance of the 87 socket for the fuel pump with and without the fuel pump connected?

Did you check for engine codes (sorry if I missed the obvious)?

[Note to self: EGR solenoid shorted to ground.]

gat

epowers777, if you do the pinout, then I'll do then pinout for the fuel pump relay, too.
If you do the wires for the fuel pump at the connector for the fuel pump, then I'll do those too.

gat

I am looking at that video and this thread on a laptop instead of a telephone. That flick seems to be coming from or around a spark plug boot in the area of the distributor's cap.
I can't finish testing my reading because I need assistance to test while cranking for the voltage at 30. The table below contains the results measured with the fuel pump relay pulled.
#, Volts, Continuity to Positive Battery Terminal (Y,Ohms, or N), Continuity to Negative Battery Terminal (Y,Ohms, or N)
30 ? Y Y
85 10.04 N 518
86 9.73 N 534
87 9.97 N N
87A - not used
Note that the battery voltage for my battery - which sits uncharged - is 10.22 volts.

epowers777

I have not forgotten about you. Thank You very much. Its been raining pretty good. Hopefully tomorrow it will stop and i can do some testing.

gat

I'm glad that we didn't run you off. If you post your values for the connector to the pump, then I'll do the same.

epowers777

I ended up pulling the NSS and cleaning it to rule that out. I didn't get the values very well as I was a little confused on your numbers. In sorry
If you stand over the passenger fender and pull the relay you have the front pin closes to engine, left side closes to cab, right side closes to battery and back closes to you.

Left side.. continuity to negative 0 ohms
Back... Continuity to negative .035 ohms
Right side....11.7 volts. Continuity to posotive
Front....12.2 volts continuity to posotive

I found a wire going to the coil and repaired it with a new plug. I pulled all the relays up and checked all wires. I removed my cruise control. Inspecting all wires on firewall. Got half way and called it quits it was getting dark.

Can you pull your relay and see if the engine cranks in every position the shifter has. Mine does it's odd..

Next I'm going to drop the steering column and check the ignition switch.
Didn't take pics of the nss