Grifter144
NAXJA Forum User
- Location
- SE Michigan
Ok so a couple months ago my DD 2000 Xj 4.0 AW4(<160,000 on the clock) started having a problem running. It would Start up run for a bit and then die. So I plugged in my cheap code reader and start chasing my tail. Codes and follow on crap sort of went like this.
1st code P1391-so get a new CKPS and an IAC / swapped em in. No change
Then code PO351 and PO352. Installed a new napa iginition rail and plugs. Still no change
It still fired up, runs for a few seconds and dies. This continued for a couple days. I finally decided somone other then me needed to fix it. So it ended up at a friend of my dads shop for 4 days. They cant figure it out (so no charge) and tell me to take it to the dealer cuz they think the PCM is bad.
3 hrs at the local dealer and I am out 400 bucks for a Diagnosis and a new cam position sensor (which they said was open so they installed a new one). This did not fix the problem and now it wont even run. They (dealer) say the motor "sounds blown".
So I take it home and yank the motor out, figuring to swap it for my old 92 MJ 4.0. Got it out and found that the flywheel had sheared from the crank leaving its center section attached to the crank, but otherwise completely seperated from the crank.
So I source a new (used) flywheel from an late model xj. My old trans smells burnt and had overheating issues so since its all out on the garage floor anyway I decide to get a low mileage replacement with a TC. I also decide while its out now would be a good time to replace gaskets on the motor, so a full gasket kit gets done too.
Swaped the whole kit, 4.0- trans and t-case back in the other day, plugged everything up and tried to fire it up. For some reason it wont fire up.
It cranks , but wont run. So I pull the timing cover to ensure the timing marks line up still. TDC on cylinder one and the crank and cam pully marks point right at each other. Chain appears good. Reassemble and try firing still no fire. But if i crank it long enough it backfires out the tailpipe.
So now I am grasping at straws.
? when installing the flywheel does it get keyed in relation to the block somehow? Is it possible the the orientation of the flywheel when being mounted would affect timing in a drastic manor?
As of today it has new
02 sensors
coil pac
plugs
flywheel
torque convertor and trans
IAC
Crank pos sensor
Cam position sensor (installed by dealer prior to discovery of broken flywheel)
and a complete motor gasket kit.
New fuel pump.
i have 12 volts at the battery and at all grounds. Judging from the back fire I have spark, and at the fuel rail I have enough pressure that if I detent the check valve it sprays all the way to the fender.
HELP?
1st code P1391-so get a new CKPS and an IAC / swapped em in. No change
Then code PO351 and PO352. Installed a new napa iginition rail and plugs. Still no change
It still fired up, runs for a few seconds and dies. This continued for a couple days. I finally decided somone other then me needed to fix it. So it ended up at a friend of my dads shop for 4 days. They cant figure it out (so no charge) and tell me to take it to the dealer cuz they think the PCM is bad.
3 hrs at the local dealer and I am out 400 bucks for a Diagnosis and a new cam position sensor (which they said was open so they installed a new one). This did not fix the problem and now it wont even run. They (dealer) say the motor "sounds blown".
So I take it home and yank the motor out, figuring to swap it for my old 92 MJ 4.0. Got it out and found that the flywheel had sheared from the crank leaving its center section attached to the crank, but otherwise completely seperated from the crank.
So I source a new (used) flywheel from an late model xj. My old trans smells burnt and had overheating issues so since its all out on the garage floor anyway I decide to get a low mileage replacement with a TC. I also decide while its out now would be a good time to replace gaskets on the motor, so a full gasket kit gets done too.
Swaped the whole kit, 4.0- trans and t-case back in the other day, plugged everything up and tried to fire it up. For some reason it wont fire up.
It cranks , but wont run. So I pull the timing cover to ensure the timing marks line up still. TDC on cylinder one and the crank and cam pully marks point right at each other. Chain appears good. Reassemble and try firing still no fire. But if i crank it long enough it backfires out the tailpipe.
So now I am grasping at straws.
? when installing the flywheel does it get keyed in relation to the block somehow? Is it possible the the orientation of the flywheel when being mounted would affect timing in a drastic manor?
As of today it has new
02 sensors
coil pac
plugs
flywheel
torque convertor and trans
IAC
Crank pos sensor
Cam position sensor (installed by dealer prior to discovery of broken flywheel)
and a complete motor gasket kit.
New fuel pump.
i have 12 volts at the battery and at all grounds. Judging from the back fire I have spark, and at the fuel rail I have enough pressure that if I detent the check valve it sprays all the way to the fender.
HELP?