On my 2003 dodge ram van 3500 the check engine light came on and the code was vacuum leak . i changed the gas cap . How do i reset the light . tried disconnecting the batterie but the light came back on after 1 day . . Question is do i need to use the scan tool to reset this code and make sure that the problem is solved . Thanks

 

You did reset light. Perhaps the gas cap was not your problem. The fact that the light was off for a day indicates that the code was cleared. When the light came back on the second time, it is now indicating a new malfunction (or a repeat of the old malfunction).

 

Harbor Freight, both online and at the local stores sell inexpensive scan tools if you are in the market for such a device. The scan tool will let you read and reset the codes. Also, most all auto stores will let you borrow one from the store will you are parked outside thier store, or someone will do it for you from the store.

 

My codes are P 0442 and P 0455 . Will have to get this looked at next week . i can't find any leaks anywhere .

 

I recall having one or both of those codes a couple of years ago. The problem was simple. I found a hose had fallen off due to a crack in the hose end. The hose was located on the black canister located on the frame under the driver side door. I cut the end of the hose off and pushed it back on to get rid of those codes.

 

Even though this is for a caravan...it will tell you what you problems are and what you need to fix...good luck!

 

RSDATA you say drivers side of the van i never checked there so i will have a look when the weather clears up . Thanks .

 

Yes, just under the door and under the front fender the evap canisters sit.

There have been issues with northern vesicles and road salt ruining the brackets and clamps.

 

For Check Engine Light codes I use the Torque App ($5) on an android device. Get a bluetooth OBDII adapter on amazon ($23) and it will let you get all of the codes and reset them. (The engine needs to be off with the switch on to reset the codes.)

Here is the adapter I bought on Amazon.com
http://amzn.com/B005NLQAHS

Here is the Torque App website:
http://torque-bhp.com/

I leave it plugged in all the time and read important engine data from the PCM while driving. Works like a charm. You won't be disappointed.