Had the CE light pop on yesterday and read the codes to get:

P0442 Evap Leak Monitor Medium (0.040) Leak Detected

What the heck does this mean? I'm fairly well versed with late EFI systems and can usually figure out and repair about anything but this one has be stumped....

Is this related to the fuel tank vapor purge system? How can I repair it?

 

have u bought any gas for your truck the last few days??? If so, tighten the cap at least 3 clicks and then unhook the battery for a few min....it'll go away if thats the problem


basically that code means there's a hole thats .040" big somewhere in the EVAP system....could be a small hole in a rubber hose or a gas cap thats not tightened all the way, somethin like that

 

Thanks Hemi, I will ask the wife and see. I don't think she got gas though as the darn thing was on empty when I got in it as usual

 

OK, I did as Hemi said and tightened the cap and reset the light but the wife called and its back on today, I can only assume its for the same code, now what? How in the heck would I go about finding a .040 hole somewhere?????

Sometimes I really hate OBDII!