Check engine light - an 01 Jeep Cherokee

[bmwgolfguy]

I have an 01 Cherokee with almost 80k miles on it. In the last two weeks the Check Engine light has come on. Both times had to do with a gas cap issue. Both occured the morning after I gassed up the night before. My mechanic says I need to buy a new gas cap from Jeep, that is the only way to stop it.

two questions.

1) How do turn off the CEL or is that something I have to have a mechanic do?

2) My mechanic says the way to stop this is to buy a new gas cap from a Jeep dealer. A cap from anywhere else won't fix it. Is this correct?

Between the times this light has come on, I filled up two other times without an incident.

Any help is appreciated.

[AlohaBra]

Just buy a cap from the parts store...I got a locking Stant for 15 bucks.

Disconnect the battery to turn off the light. Or borrow the code checker from the Parts store.

Get a code if you can just to make sure it is the gas cap. The NSS will set a CEL with the mileage your Jeep has on it.

[bmwgolfguy]

Alohabra:

As always, your input has been valuable.

I disconnected the battery and that got rid of the light. Thanks.

I am going to get a new gas cap this weekend. Will most auto parts stores carry them? Who would you suggest.

Thanks again.

P.S. How did come up with your handle on this site?

[AlohaBra]

Any brand name store that carry Stant brand should have one.

[bmwgolfguy]

Thanks Aloha.

I replaced the fuel cap and the light is back on. I believe the error code was "P0456-Evap Leak Monitor 0.020" Leak Detected".

I have a basic understanding of what the EVAP system is and what it does. I am just wondering, given the code above, what kind of money range am I looking at potentially to make this problem go away?

Thanks