CHRYSLER DODGE JEEP LEAK DETECTION PUMP P0455 LARGE EVAP LEAK 

Been repairing LDP systems for a long time now and always wondered why Chrysler used vacuum to make pressure. Pretty failure prone system at that. The NVLD's aren't that much better either and to think now we have the lovely ESIM system haha hey 3rd time is a charm right!? Any how great vid James and good demo with the rubber glove :)

HAHAHA the inflating rubber glove cracked me up! It was showing us the finger LOL! FREAKING BRILLIANT! Great explanation of the LDP system in theory and practice. Mitchell seems to have great info here...AllData has similar content, but that TSB wasn't even listed! Had to go to the FREE BBBindustries site to look it up.

My takeway: pump the system with air and listen for a hissing sound. I have 0455 gross (large) leak problem on 2003 Grand Cherokee. Last of 6 codes to fix. Hoping to find the offending problem soon so I can pass NJ's stringent inspection process. Failed twice already. Wish me luck, guys.

so running the evap test with the scanner will show codes that would come up eventually from driving for a few days? in the bay?

Have this code on my '01 TJ and am still beating my head against the wall trying to clear it. Bypassed a rotten steel vent line - of course that must've been it, right? Of course it wasn't. I'll make my decision after I finish watching this but I suspect it will be the LDP, mostly because that would be the most expensive part to replace, haha

Thanks James been messing with my 01 tj got small leak and pinched hose codes thought they were kind of conflicting codes left me a little confused so have been researching operation of LDP. also replaced same line to tank, southwestern Ontario rust belt. got to get an etest here soon your video helps a lot and perfect timing, Thank you, love the glove test cool.

Danner send me a message with links to things you need maybe from Amazon up to $40 with an address to send them to.

Nice vid buddy, I like the visual of the glove too. 👍👍

Nick or clark one of them will always bug you at the wrong time ha ha !

Lol this represents my sex life

excellent. More stuff to buy? The problem some are worried about with using air pressure then causing explosions is not so much the air but the pressure. I found I think on E bay a water pressure gauge that I could tee in like you did with the old fuel pressure gauge. You can then see accurately the much lower pressure required to safely do the test. Keep going.

thanks for the info....excellent video

Nice video. You should really appreciate your boss allowing you to have so much fun at the shop. The green cap on the EVAP system signifies an enhanced evaporative control system. All enhanced EVAP systems’ Schrader valves have left hand threads. In the “do as I say, and not necessarily as I have done column” observing safe practices dictates that injecting air, rather than Nitrogen, into a fuel system is very dangerous practice because it is a fire hazard! Therefore, proceed with caution (The shops I have worked at do not want to spend the money on the Nitrogen). My available information on the Chrysler LDP is the time between LDP solenoid off and LDP switch closed is called the “Pump Period.” The shorter the Pump Period, the larger the leak. The longer the Pump Period, the smaller the leak. Large leak (>0.080) Pump Period is 0.9 seconds. Medium leak (0.040 to 0.080) Pump Period is 0.9 to 1.2 seconds. Small leak (0.020 to 0.040) Pump Period is 1.2 to6.0 seconds. Finally, throw a vacuum gauge on the ’57 Chevy and see how much vacuum develops at idle and up through 1800 rpm. If it has an aggressive camshaft I predict it will not have much vacuum at idle, but as rpm increases vacuum will increase.

Hey jimmy what's going on? You got to much to do you forget us? all your loyal fan's!!

Great video on theory and operation, Jim. Nice fix as well.

😎😎😎😎😎😎😎

jim i asked your brtherl what was up with you and you knoq what he told me i quote i am not my brother's keeper we have to get him for that what do you think? Check his last video.

Hey there is that cool 57 chevy i seen there back when you did paul's truck nice.