Hello; I have a 2002 dakota with truoble codes po442 and po455. I know its part of my evap system. Any suggestions on where to start looking.

 

I will move this to the 2nd generation Dakota sub-section.

 

Welcome to the forums Matt.

P0442 - Evap leak monitor medium leak detected
P0455 - Evap leak monitor large leak detected.

Check the gas cap. Yes, they can go bad.
How are all the evap lines? Look for cracks. Check the filler neck for rust too.

 

i second the gas cap, very common. did you get fuel today?

 

Check the emissions hoses at the charcoal canister. It is located under the bed of the truck just forward of the gas tank. The curved hoses on the canister are known to crack and split which can set evap system leak codes. Also check the emissions hoses under the hood, particularly at the green evap test port above the left side valve cover. Back when my truck threw the P0442 code I found bad cracks in the hoses at the test port. Rather than chasing the rest of my hoses looking for cracks, I just bought about 7 feet of emissions hose at the parts store and replaced all of the emissions hoses under the hood. I also replaced the right angle hoses at the evap purge solenoid too. The cause of my P0442 code turned out to be a bad emissions leak detection pump, but it was damaged when I was in an accident and took a bad hit in the front end.

About a year ago I replaced my gas cap too, but not because of any codes. I had my truck in my garage one day and my wife noticed a faint gas smell. It was coming from the gas filler area. A new gas cap took care of the gas fumes leak. Gas caps are known to leak and even the smallest leak can set a code. A good garage can do a smoke test on your truck if you are unable to find the source of your leaks/codes.

Jimmy

 

Hello all: Thanks for the info from all of you. I got a knew gas cap and reset my comp. I have drove for about 30 mils and no engine light. Hope that did it.

 

next time before you buy, just make sure your cap is clicked or tight. alot of people who go to full serve stations, the gas jockey doesnt turn it all the way, thus acting as a leak.

not that they're expensive but just something to remember