ok so my CEL light is on and i got the code P1494 (M) Leak Detection Pump Sw or Mechanical Fault Incorrect input state detected for the leak detection pump (LDP) pressure switch. i have a 02 3.9 2wd auto, what and where is this pressure switch? is it ok to drive like this until i get it fixed, the trucks seems fine but i dont want to risk it, Costly?

any help is much appreciated

 

bumpey

 

Mine comes on and i clear it by either a NEG terminal disconnection or a scan tool at advance it's either beside battery or under battery, comes back on though, still drives and runs fine, according to manual (which you can download thru this site), it's a monitoring type of sys for vacuum sys, letcha know when i figure out how to fix it, found the answer from a previous post while searching threads for 1494

 

The LDP is mounted on the bottom side of the battery tray. You have to remove the battery and unbolt the Power Distribution Center so you can move it up out of the way and remove the battery tray from the truck so you can R&R the LDP.

The LDP receives a command every so many minutes of engine operation to check the evaporative emissions system for leaks. On my truck it does it once every 70 minutes of engine run time. If a leak is detected, it triggers the check engine light. Around here a new LDP costs about $130.00 at the Dodge dealer. When I got a P0441 code on my truck last year I found there are about 6 or 8 different possible causes for that code. The LDP failure is one of the possible causes but I did not want to spend $130.00 and have it not fix the problem. I bought a LDP off a "Cash For Clunkers" Dakota at a local junk yard for $20.00. I also replaced all the emisisons hoses under the hood with fuel hose from the parts store, it took 7 feet of hose. I also replaced the two right angle hose connectors on the emissions purge solenoid, which is mounted on the fender well between the battery and the left headlight. Then I did a hard reset on my PCM and have not seen the code since. That was back in April of last year.

You can continue to drive with the LDP code and CEL on but it is not a good idea. Anytime the check engine light is on, it is best to find the problem and fix it. That is not only so the truck runs right but you need the CEL to be working correctly so it can alert you to any other problems that might come up later. Also if your city or county has vehicle or emissions inspections, your truck probably won't pass with the CEL being on.

Jimmy