[ID89YJ]

I'm about to lite a match to it, i'm discusted. The problem i have is i am using a 92yj harness and everyone else uses xj. I can't get any spark. the auto shut down relay has power to 30, 85, and 86 terminals which has me puzzled. There should only be power to 2 of those and 1 should be a ground. The other problem is no one can tell me which wires on the yj harness is the 5 wires to fire.


Help????

Steve

[sentinal02]

Originally Posted by ID89YJ

I'm about to lite a match to it, i'm discusted. The problem i have is i am using a 92yj harness and everyone else uses xj. I can't get any spark. the auto shut down relay has power to 30, 85, and 86 terminals which has me puzzled. There should only be power to 2 of those and 1 should be a ground. The other problem is no one can tell me which wires on the yj harness is the 5 wires to fire.


Help????

Steve

if you've got power to both pins 85 and 86 with the key off, you've got a short on one side. one of those pins (probably 85) will connect to pin 51 on the ECU and is the ground trigger that the computer provided to pull in the relay. with the key on you'll see voltage at both pins since it will brisge the coil on the relay and keep on going to the computer.

as for the "5 wires to fire" i've never heard that phrase. care to elaborate?

[ID89YJ]

Originally Posted by sentinal02

if you've got power to both pins 85 and 86 with the key off, you've got a short on one side. one of those pins (probably 85) will connect to pin 51 on the ECU and is the ground trigger that the computer provided to pull in the relay. with the key on you'll see voltage at both pins since it will brisge the coil on the relay and keep on going to the computer.

as for the "5 wires to fire" i've never heard that phrase. care to elaborate?

I had the key on so i guess it is correct. I may hace a cps sensor problem. The 5 wires for fire is a saying people use when swaping 4.0l in older jeeps. That relay never does click, i will search the cps problem and see what happens.

Steve

[ID89YJ]

At this point i'm wishing i would have put a small block chev in there. I think i may end up buying the Hesco harness to complete this.

Steve

[Why J?]

Are you going from a 2.5 to a 4.0? or was it a 258?

[ID89YJ]

Was a 2.5l, i bought the jeep with a bad engine.


Steve

[Why J?]

I am not sure how much help I can be but I have the 87-90 chrysler student teaching guide with all the info you could ever need to know about the injection system on the 2.5L. It list all the diag points and wiring schematics for each year and the variants between each year. Anything you need to know I'll see if I can find it for ya.

[Why J?]

Just a though, there is a feature on most the FI jeeps that if the WOT is showing closed as in you are in WOT it will not fire. It is a feature for clearing a flooded engine. If you have not wired in that sensor yet or not correctly, it will not fire.

[sentinal02]

Originally Posted by Why J?

Just a though, there is a feature on most the FI jeeps that if the WOT is showing closed as in you are in WOT it will not fire. It is a feature for clearing a flooded engine. If you have not wired in that sensor yet or not correctly, it will not fire.

the mpi engines don't use a WOT switch. all done with the TPS.

Steve did the engine run when you pulled it? where exactly does the spark path stop? if you don't get anything from the coil, and you have power out of the ASD relay then you've either got a break in the wire feeding the coil or the coil itself is bad. if it's further down the line then it could be the cap, rotor plugs, etc. a lot depends on where the spark path is interrupted.

[ID89YJ]

Thanks for the idears guys but i got it figured out last night and it was a bad cps. She purrs like a kitten now.

Steve