I bought a 1990 YJ a few weeks ago and need a little help getting it running. I believe motor came out of a 90 xj
The jeep had a 4.0l engine in it when i bought it, the guy i got it from got it from another guy so there isn't any way to get a hold of the original person that did the swap. First problem found was that the bulkhead firewall connection for the wiring harness from the engine was plugged into the YJ firewall and wires did not match up correctly. As of now i have two power sources from the engine harness plugged into the firewall for power inside the cab. I have a yellow wire that powers the PDC ,(4 relays under hood) and various other things like coil and such, that wire is switched on with the ingnition switch. And the only other wire running between the engine wiring harness and YJ firwall is the signal wire for the starter relay. After a day of tracing wires to figure this out i went to a junk yard and pulled a new harness that wasn't hacked up and also got everything hooked to the harness that i thought i would need. ECU, sensors, some metal box that the wires ran through the firewall and was mounted under the glove box? I can't find any good diagrams and the local dealer didn't want to give me the time of the day. I did not pull the distributor or coil from the junk yard XJ.
So after installing new harness i realized that there was no Crank postion sensor installed, but there was a spot in the bell housing for it. I have since installed sensor. Next problem was that the guy tried using a cheap fuel pump mounted under the hood to supply fuel to fuel rail. Well after i took the clamp of the pump i could see the sticker said it was rated for 9 psi. Found a stock YJ tank for a 4.0l an have installed and wire directly to battery with switch temporarily.
Sorry for the long info. just wanted to give all the background info.
So my problem is that when i try to start the engine it turns over several revolutions before starting, each time it sounds more and more like it is going to start till it finally hits a lick. The next and more major problem is the fact that it dies after about 2 seconds. I know your thinking it is a security thing but before you say that, it is a 1990 model engine. Did they have any security devices on jeep that model year? The only thing i have read is on the obd ll engines that have the security feture. The other reason i'm not so sure that is the issue is because i had 2 ecu's that came with the jeep and the one from the junk yard, they all give me the same result.
So is did xj's come equipped with a security device on that year or do i have another problem. I know of about 2 more jeeps in the yard with the same computers but i don't want to spend anymore money on a computer since i have three of them.
Again sorry for the long post, but any info you can give me would be much appreciated!
Thanks,
Nick
The jeep had a 4.0l engine in it when i bought it, the guy i got it from got it from another guy so there isn't any way to get a hold of the original person that did the swap. First problem found was that the bulkhead firewall connection for the wiring harness from the engine was plugged into the YJ firewall and wires did not match up correctly. As of now i have two power sources from the engine harness plugged into the firewall for power inside the cab. I have a yellow wire that powers the PDC ,(4 relays under hood) and various other things like coil and such, that wire is switched on with the ingnition switch. And the only other wire running between the engine wiring harness and YJ firwall is the signal wire for the starter relay. After a day of tracing wires to figure this out i went to a junk yard and pulled a new harness that wasn't hacked up and also got everything hooked to the harness that i thought i would need. ECU, sensors, some metal box that the wires ran through the firewall and was mounted under the glove box? I can't find any good diagrams and the local dealer didn't want to give me the time of the day. I did not pull the distributor or coil from the junk yard XJ.
So after installing new harness i realized that there was no Crank postion sensor installed, but there was a spot in the bell housing for it. I have since installed sensor. Next problem was that the guy tried using a cheap fuel pump mounted under the hood to supply fuel to fuel rail. Well after i took the clamp of the pump i could see the sticker said it was rated for 9 psi. Found a stock YJ tank for a 4.0l an have installed and wire directly to battery with switch temporarily.
Sorry for the long info. just wanted to give all the background info.
So my problem is that when i try to start the engine it turns over several revolutions before starting, each time it sounds more and more like it is going to start till it finally hits a lick. The next and more major problem is the fact that it dies after about 2 seconds. I know your thinking it is a security thing but before you say that, it is a 1990 model engine. Did they have any security devices on jeep that model year? The only thing i have read is on the obd ll engines that have the security feture. The other reason i'm not so sure that is the issue is because i had 2 ecu's that came with the jeep and the one from the junk yard, they all give me the same result.
So is did xj's come equipped with a security device on that year or do i have another problem. I know of about 2 more jeeps in the yard with the same computers but i don't want to spend anymore money on a computer since i have three of them.
Again sorry for the long post, but any info you can give me would be much appreciated!
Thanks,
Nick