DMS3XJ
NAXJA Forum User
- Location
- Monterey Bay
Anyone care to help me diagnose my renix no start this xmas eve?
I've seen this covered many times and it seems to often pan out to something simple like a bad ground, but I'm hoping I can provide some clues, and renix folk might be able to point me in the right direction to find the culprit more efficiently. Also after all the threads to this end with no conclusion I promise to post my solution lol.
SO, 89 xj 4.0 auto 155k miles. I have had a no start twice, ONCE a few weeks ago after changing my exhaust manifold, put everything back together, and it would turn over but not catch. Left it in the sun for a day and it fired up fine, no problems since.
THIS time I reinstalled a t-case drop after installing a new tcase with an sye and forgot about needing to adjust pinion angles, so I put the drop back on on a cold drizzly morning: Ran fine after the new tcase, no start after just lowing the crossmember and reinstalling case drop. Didn't even open the hood.
Diagnostics.
1) CPS seems okay, I had a fairly new one when it wouldn't start. I switched in my NAPA spare, still no start. I have what appears to be a weak? yellow spark at the plugs. I swapped ICM with another and it had no effect. Dist, cap, rotor, wires and plugs are pretty new and indexed correctly a la cruiser54 tips.
2) Fuel pump is not priming. But it's running fine during cranking, no pressure at the schrader valve at prime, but there is pressure after a failed crank.
3) Tachometer has almost no movement and the battery gauge is inaccurate.
From reading other posts this seems to point to the b-latch relay or some ground. I have tried switching it around with other relays and I have't been able to get a fuel prime. The ground at the dipstick has been cleaned. I haven't yet checked for power at the b-latch relay to the ECU. Block to frame ground is looking kinda mucky.
I'm hoping someone can point me in a direction with specific targets to test. Where to start? Proper way to test relays? Any specific fuses I should look at and their locations? I have an multimeter and can report voltages/resistances.
I've seen this covered many times and it seems to often pan out to something simple like a bad ground, but I'm hoping I can provide some clues, and renix folk might be able to point me in the right direction to find the culprit more efficiently. Also after all the threads to this end with no conclusion I promise to post my solution lol.
SO, 89 xj 4.0 auto 155k miles. I have had a no start twice, ONCE a few weeks ago after changing my exhaust manifold, put everything back together, and it would turn over but not catch. Left it in the sun for a day and it fired up fine, no problems since.
THIS time I reinstalled a t-case drop after installing a new tcase with an sye and forgot about needing to adjust pinion angles, so I put the drop back on on a cold drizzly morning: Ran fine after the new tcase, no start after just lowing the crossmember and reinstalling case drop. Didn't even open the hood.
Diagnostics.
1) CPS seems okay, I had a fairly new one when it wouldn't start. I switched in my NAPA spare, still no start. I have what appears to be a weak? yellow spark at the plugs. I swapped ICM with another and it had no effect. Dist, cap, rotor, wires and plugs are pretty new and indexed correctly a la cruiser54 tips.
2) Fuel pump is not priming. But it's running fine during cranking, no pressure at the schrader valve at prime, but there is pressure after a failed crank.
3) Tachometer has almost no movement and the battery gauge is inaccurate.
From reading other posts this seems to point to the b-latch relay or some ground. I have tried switching it around with other relays and I have't been able to get a fuel prime. The ground at the dipstick has been cleaned. I haven't yet checked for power at the b-latch relay to the ECU. Block to frame ground is looking kinda mucky.
I'm hoping someone can point me in a direction with specific targets to test. Where to start? Proper way to test relays? Any specific fuses I should look at and their locations? I have an multimeter and can report voltages/resistances.