My 99 2.5 is suffering P1495 - VAP Leak Detection Pump Solenoid Circuit Condition and I just cant seem to resolve it. I believe I have narrowed it down to be definitely an electrical issue but have hit a dead end. Here is everything I have tried;
-Checked for vacuum leaks via smoke test no blatant ones found
-Replaced all sketchy looking vacuum connectors anyway.
-Disconnected the evap line that runs back to the fuel tank, slightly pressurized it with an air compressor and capped it off. It was still holding pressure a few hours later. This line was also replaced because it rusted out awhile ago.
-Put a test light on the ground pin of the connector, good ground.
-12v on the second pin, 3rd pin I'm not sure how to test? 4th pin is unused according to diagrams and due to the fact that the ldp does not have a receiving pin for it.
- Peeled back the plastic insulation and inspected the wires back to where they reach the main harness, didn't notice any damage.
-Borrowed a buddies LDP and purge solenoid that are know to be working and swapped them, no change.
-Checked the related fuses, both were good and swapped them anyway.
Some things to note;
-When i reset the CEL, the code comes back immediately with just the ignition being on, engine not running.
-I recently finished putting this jeep back together after a complete resto and engine rebuild and this code did not exist before hand, same pcm but is a new electrical harness as the old one was accidentally severed at the firewall. New used harness matched all the specs of the old one though.
-After the rebuild i managed to install the purge solenoid upside down and failed to notice until recently, I'm not sure how much this would affect the LDP.
-It's entirely possible I have vac lines in the incorrect positions though I believe I have them all right.
How do i go about trouble shooting this further? My knowledge with a multimeter is limited and really only know how to check voltage. Thanks in advance
-Checked for vacuum leaks via smoke test no blatant ones found
-Replaced all sketchy looking vacuum connectors anyway.
-Disconnected the evap line that runs back to the fuel tank, slightly pressurized it with an air compressor and capped it off. It was still holding pressure a few hours later. This line was also replaced because it rusted out awhile ago.
-Put a test light on the ground pin of the connector, good ground.
-12v on the second pin, 3rd pin I'm not sure how to test? 4th pin is unused according to diagrams and due to the fact that the ldp does not have a receiving pin for it.
- Peeled back the plastic insulation and inspected the wires back to where they reach the main harness, didn't notice any damage.
-Borrowed a buddies LDP and purge solenoid that are know to be working and swapped them, no change.
-Checked the related fuses, both were good and swapped them anyway.
Some things to note;
-When i reset the CEL, the code comes back immediately with just the ignition being on, engine not running.
-I recently finished putting this jeep back together after a complete resto and engine rebuild and this code did not exist before hand, same pcm but is a new electrical harness as the old one was accidentally severed at the firewall. New used harness matched all the specs of the old one though.
-After the rebuild i managed to install the purge solenoid upside down and failed to notice until recently, I'm not sure how much this would affect the LDP.
-It's entirely possible I have vac lines in the incorrect positions though I believe I have them all right.
How do i go about trouble shooting this further? My knowledge with a multimeter is limited and really only know how to check voltage. Thanks in advance
