LDP Leak detection pump. Just looked it up in the Ram manual. Now I'll have to read up on it's operation.

 

they are very commonly replaced....maybe its a dodge thing...

 

What does it do? Any ideas?

 

there is actually a longer name...it monitors the emissions evaporative system...i will find out more detail tomorrow..

 

Oh, Oh.
I know, I know!!!

 

well, then tell us!

 

It does just what it sounds like. The canister purge solenoid is commanded closed and then the LDP applies a small amount of pressure to the system(usually less than 3psi), most have a pressure sensor in them to detect any drop in pressure(leak) and the rate at which it drops is compared to predetermined threasholds to determine your gross or small status.
Simple version, It checks the vapor recovery system for leaks. OBDII crap.

 

Then it puts pressure to the tank as well if it can detect a faulty gas cap seal. Thanks for the information.

*walking away scratching head.* And I thought today would be the day I didn't learn a thing.

 

OBDII crap indeed...[:@]

if it is the LDP...
pn-4891419AA
cost-57.00
list-95.00
lots available...

 

Vapor recovery sys includes the tank and filler neck nowadays, since OBDII.

Too bad it was ODB that died, not OBD! Just a thought.