Hey everyone, I've posted this on another forum, hopefully I'll have better luck here.
I have a 97 Tj 4.0 with a check engine light that has me stumped. The code is p1494 [Leak Detection Pump Switch or Mechanical Fault. Incorrect input state detected for the Leak Detection Pump (LDP) pressure switch]. I have been reading and searching for months to no avail. Hopefully someone here has an idea that i have yet to try.
So far, heres what i have tried/replaced:
-Gas cap x2
-leak detection pump x2
-Replaced ALL the lines in the evap system
-Charcoal canister
-cleaned up the ground for the PCM and added as secondary jumper to the battery
Im no expert in electrical so forgive me if I get some things wrong. Ive checked the OHMS on the sense side of the circuit and checked out at .02. The power side was showing 13 and some change while running.
Also, when I checked the vacuum on the manifold side, I got 14in HG.
I know its not the PCM because it continued after I swapped in an auto with PCM. I dont think it can be the gas tank itself due to the vacuum on it after trying to bypass the evap canister.
If anyone has any ideas I can try or retry I'm all ears. I've been riddled with this issue for months and inspection is coming up.
I have a 97 Tj 4.0 with a check engine light that has me stumped. The code is p1494 [Leak Detection Pump Switch or Mechanical Fault. Incorrect input state detected for the Leak Detection Pump (LDP) pressure switch]. I have been reading and searching for months to no avail. Hopefully someone here has an idea that i have yet to try.
So far, heres what i have tried/replaced:
-Gas cap x2
-leak detection pump x2
-Replaced ALL the lines in the evap system
-Charcoal canister
-cleaned up the ground for the PCM and added as secondary jumper to the battery
Im no expert in electrical so forgive me if I get some things wrong. Ive checked the OHMS on the sense side of the circuit and checked out at .02. The power side was showing 13 and some change while running.
Also, when I checked the vacuum on the manifold side, I got 14in HG.
I know its not the PCM because it continued after I swapped in an auto with PCM. I dont think it can be the gas tank itself due to the vacuum on it after trying to bypass the evap canister.
If anyone has any ideas I can try or retry I'm all ears. I've been riddled with this issue for months and inspection is coming up.