Ok heres the rundown to date on whats been done to my truck. '06 ram 5.7 hemi with mds. magnaflow cat back with split dauls, air raid throttle body spacer, k&n fipk kit, superchips flash paq tuner. The truck was new when these were installed by my shop, we have installed many of these same upgrades on 100's of trucks with no issues like mine. I am continually getting a code about a fuel vapor leak. I can read the codes and reset them with the tuner but this is tiring. I put a new gas cap on just to eliminate that possibilty. I took it into the dealer, they had it for a day then tried to charge me $100 and said it was because of the modifications I made. I have installed a lot of aftermarket parts and never had this issue before, but heres the sad part after removing all aftermarket parts the service light still comes on. Any ideas before I take it in and leave it with these eggheads.
Thanx for any ideas,
Jeremy

 

Remove the TBS completly!!! Reset the tuner to stock and take it to a different dealership. Never take your truck in without reseting the computer back to stock!!!! Once they see u have messed with the cpu, it'll void alot of your warranty!
Also check for any welding leaks on the new exhaust.

 

Fuel Vapor leaks come from a few different spots. The main culprit is the gas cap. Obviously you have tried that. There are also some rubber hoses that wear out over time that are associated with the fuel system that can throw those codes. If you do a search, you can find more info about those.

I seriously doubt your mods caused the code. Also, as mentioned, return your truck back to stock tune before you bring it in, especially, in case they decide to do a software update and your flashpaq info is lost and your tuner will be of no use.

 

My 06 1500 Quad Cab 4x4 5.7Hemi kept giving me a vapor leak signal as well. To make a long story short, had them smoke the gas tank to check for leaks and finally found it to be a faulty gas tank. Was leaking around one of the return port areas. Had to have the tank replaced, no more troubles.

 

This is interesting. Wonder if mine is the same. It has progressed from a 456 to a 455 to a 440...general evap fail. Before I go buy a pump, I'm going to try to take my gas cap off, get an air hose and put my regulator on about 3 psi and seal the hose into the filler line, and then poke my head around the tank and see if I hear air coming out. Only 3 psi 'cuz I don't want to blow stuff apart!