awg

I was thinking the above and mentioned it

The OP should enter his PCM number into Google and find out

for instance most 4.0 PCM start with 56041xxx.

This is printed on the metal case

They also would have had to change out the ignition barrel to make it work. Is it changed ?

What may have happened is someone made changes, and could never get it to work

Has it ever run ??

One thing I am sure of is a 6cyl PCM could not run a 4cyl engine without a mile of CELs, if at all

we need more info, including pics of things i have asked about

dmoe69

Perhaps I just don't understand what engines Chrysler Corp sold in '97 XJs outside of the US. But a 6-cylinder PCM trying to fire every 60 degrees isn't going to be able to manage a 4-cylinder that needs to fire every 90 degrees.

dmoe69

It looks like Jeep did sell 2.5L in fleet vehicles (Park service, police, etc.) in 1997, so it's possible...

Saudade

ICYMI, the OP is in Norway.

awg

pictures!

Martin86Cherokee

Quick update: It runs!

The immobiliser is definitely the issue and I'm not sure exactly what I did to make it work so my guess is a loose wire somewhere. Luckily the immobiliser isn't fried. After getting it to start I tried disconnecting the immobiliser unit and the car cranked, started, died just like before, reconeccting the immobiliser made it start right up. The guy I bought it from said he was never able to make it start, he had bought a new ASD relay, but put it in the wrong spot. He had partially disasembled the dash/doors looking for the immobiliser, but must not have found it. He had pulled some fuses, including the one for the instrument cluster which I think is part of the reason why he couldn't get it to start.

The first thing I did when I got it home was to connect the ASD relay in the right spot and it cranked, started and then died. I could hear the fuel pump priming the system when I turned on the ignition but then it would cut out. When I tried jumping the fuel pump I blew a fuse which made me look through all the fuses and indeed some were missing. After pulling the center console out, I found the immobiliser. The immobiliser harness is connected to the interior fuse box on the passenger side. From the harness there are two sets of black/red wires, one set goes through the firewall and is spliced into one of the connectors to the ECU, the other set is spliced into some wires on the OBDII port and from there it is run behind the dash and is spliced (yet again) into one of the connectors to the instrument cluster. Other than a loose connection I'm thinking that the reason the last owner wasn't able to get it started was a combination of the ASD relay being placed in the wrong spot (no start issue) and the fuse for the instrument cluster being pulled causing the ECU to not get a signal from the immobiliser and cutting the power to the fuel pump. Sadly for the last guy it may just have been a bad ASD relay and when he got the new one he plugged it in the wrong spot which caused him to start digging around the dash and taking out fuses.

I'll get some pictures together with what I've been able to figure out. All I was told when I bought it was that it's an 86 with a 95 dash and wiring harness so I've had to do a lot of research and digging around. After going through the car, a lot of parts come up as being from a 97, the ECU, Engine (block is manufactured in 95), valve cover and air filter housing looks different, it has a more modern crank position sensor (connector is different), Transfer case is manufactured in 97(not sure about the transmission, haven't found any markings on it yet). That's why I've concluded that most likely the dash, wiring harness, ECU, engine, transmission, transfer case etc is out of a 97. The immobiliser I found is slightly different from the SKIM system where there is a coil around the ignition barrel. From what I could find it seems like this system was used in 1997-1998 as an optional acessory before they introduced the SKIM system. This is just based on comments I have found on various forums etc so don't take it as fact, but it seems to add up.

I'm pretty excited to get it running, but I also wish I knew exactly what I changed to make it work. Ideally I'd be able to delete the immobiliser, but I'm just going to take a while to think about how I want to move forward. I consider this a restoration project so I want it to be as original as possible. The plan is to strip the interior, weld all the rust I can find, add some sound deadening material, reglue the headliner, find a year-matching drivers seat, rebuild/service as much of the car as I can.

Sorry for the information dump/ramble, I'll try to gather all the information I have found in a more presentable way along with parts numbers etc.

awg

wait !

does it run continuously, or just start and die after 3 secs?

The 97 Immobilser for "Export models" (ie Australia where I am from) is unique

So I have read on our forum, the 98 and later had a different system

I am fairly sure this can be confirmed by downloading the Parts Manual

That is why 97 models (in Oz) are usually stuffed if the immobiliser goes out (that is cause you need a matching PCM and ignition barrel from a 97 only)

You may have a 98 or later immobilser

Is it running full time ?

Martin86Cherokee

It starts and stays running! Doesn't sound bad either and no check engine or other warning lights.

If I disconnect the immobilizer it goes back to shutting down after 1-2 seconds. The car has been sitting for a couple years I think without running so I'm a litte unsure if I should do a coolant flush/check the gas etc on it before letting it run and get to temperature. There coolant has seen better days and the reservoir is quite low. There are also quite a few connectors that are just sitting in the engine bay and behind the dash that I haven't had the time to identify. Someone cut the bottom out of the charcoal cannister and a few other interesting bits and bobs.

In the parts catalogue for 1997-99 I can find the part number for the immobilizer but in the illustration it shows the ignition barrel, no picture of the circuit board that I posted a picture of earlier. The little black transponder that was taped to the circuit board does not seem to affect the car being able to start or not, maybe it has more range than I tested it with, but at least it doesn't have to sit right next to the immobilizer or ignition barrel.
Trying to read up on the 1997 system on ausjeepoffroad.com to see if it's the same as what I found but I get this message "AJOR is upgrading it's software. Sorry for any inconvenience" so I guess I'll have to wait!

awg

Good job mate

Check the parts manual for 98 "Export models"...that may show you have the immobiliser that was fitted 98-01

I have heard that some folk were able to gets theirs running somehow much like you have done, which appears to "trick" the PCM

If that works, all power to you

I think you will need to study the Parts Manuals and FSMs for relevant years, and I am confident you will be able to get it going

My advice is make extensive notes on any wiring anomalies you find or make, tag all new wires with electrical harness tags.

No one else but you will be able to fix it I suspect