Truck = 99 Dodge Durango with a 5.9

Ok here we go. Check engine light has come on for the past week straight every time I hook a scanner up to the obd2 port and check the codes it says no codes found pass. Ant idea why the light would be on with no codes? and btw the truck is running great have noticed no loss of power or anything different with the truck. Any advance other then black tape to cover it lol

 

Gas cap?

Alt voltage?

Bad gas (O2 sensor coming and going)

Old age on ANY of the sensors coming and going.

If drivability is unaffected, and the light goes off without storing codes, just drive it. Once it fails enough to force the PCM to store the code, it will be fixable with a path to the problem. The bread crumb trail now... with the birds eating the crumbs along the way... gets us no where but lost.

IndyDurango

 

I would check you air/evap lines (theres an right up on here) Its just an guess, plus it doesnt hurt to make sure none of your evap lines are cracked.

 

Take it to Auto ZOne or Checkers and get a newwer code reader on it and see if you can pick up the code. Yours might not be compatible or is not picking up a shadow code for some reason.

 

the scanner im using is a snap on solus pro, its not old or junk, but it still doesnt find the codes, o2 sensors are switching great its not running rich or lean. oh well i will just drive it till it stores a code