The check engine light came on today. I went to AutoZone, and the reader said P1494 Leak Detection Pump Switch or Mechanical Fault.
So, what’s leaking?
The wagon runs great otherwise. Do I need to get this fixed by a mechanic right away, or can I wait?
P1494 (M) means there’s a problem with the Leak Detection Pump (LDP) pressure switch. It’s detecting an incorrect input state, which might mean the LDP switch is faulty or the pump itself has an issue. You should check the pump, its wiring connections, and the hoses attached to it.
LEAK DETECTION PUMP (LDP) OPERATION:
The Evaporative emissions system keeps fuel vapors from escaping into the air. It checks for leaks and blockages in the system. During diagnostics, the Powertrain Control Module (PCM) first checks the LDP for electrical and mechanical problems. If those checks are fine, the PCM uses the LDP to seal the vent valve and pump air into the system. If there’s a leak, the PCM continues to pump air to replace what’s escaping. It measures the size of the leak by how long and how fast it has to pump to keep the system pressurized.
Wow, the LDP.
I’ve never heard of that before.
Is it just related to emissions? Doesn’t affect how the engine works?
So I can put off seeing the mechanic?
Nice picture, by the way. It’ll help with my own troubleshooting. I should probably get a manual or download one. The problem is, my wife is always on the computer, and I don’t have a printer.
The leak detection system is related to emissions. It’s not critical, but it’s a good idea to address every code you get.
If you don’t, and then you get another code, fixing the new problem will be more complicated.
Also, consider getting a printer. I just bought a cheap one for $30.
I had the same error code. I replaced all the rubber hoses from the purge solenoid to the gas tank. I took some old pieces to the auto parts store and bought a foot of each size. Make sure you get hoses for fuel vapors. It took a bit over an hour to replace everything. Three months later, and I haven’t had a check engine light.
Thanks. It looks like I have a weekend project coming up. If it takes a normal person an hour, it’ll probably take me three.
I’m getting this code, but my TJ (2002 4.0) actually dies. It starts up fine, but then it sputters and shuts off after a few seconds. I had the clutch master cylinder and clutch replaced 99 miles ago. Any ideas?