Nope, I just called the parts counter at the dealer and asked if he had one and how much. I am going to get it tomorrow though.

 

Isn't the emission system warranty 50K or 5yrs?

 

There is no single answer to that question.
Different emission parts are covered for different lengths of time.
2yr/24k; 8yr/80k; 3yr/50k; 7yr/70k;

It also depends on if the Jeep was built to comply with California Emissions standards.
(If your vehicle is equipped with a California Certified
Emission Control System and is registered in California,
Massachusetts, Maine, Vermont, Connecticut, Rhode
Island, or Pennsylvania, the California Emission
Warranty — described in Section 5.3 — also applies.)

 

I had the same thing as most complaining about the evap system. Mine first started with a GASCAP message. After a trip to the dealer they reset the error and it returned a couple days later, this time followed by P0440. Well it didn't take long before I got the P0442 and the failure P0455.

So after reading this thread I thought I would first try a smoke test. Guess what? No leak!

Ok I thought about replacing all the evap parts. I started with the cheapest the part the pressure sensor. it is twist locked onto the evap canister about $10. Reset my computer and presto, problem fixed. Been 2000 miles.

The piece I replaced is that little white box.




However, I wanted to know what the hell went wrong. This is what I discovered and it wasn't easy that little bugger is glued shut and I didn't want to contaminate it with saw dust.

That little box is a sensor. It has a plunger inside with a rubber gasket making a tight seal. Once pressurized it stays in place and sends the signal to the computer that the system is in fact pressurized. I theorize that some of the charcoal dust from the evap canister got through the filter and lightly coated the insides of sensor housing and the rubber seals preventing it from maintaining a tight seal; minimal at first but as it got dirtier it became worse. Charcoal dust although not thick was apparent and prevented a tight seal when I applied a vacuum.

The pressure sensor is a simple device with only one set of contacts in it, no electronics or corrodible components. Mine is now working but I live in Mexico and drive a lot of cobble stone roads which must be vibrating the hell out of that poor evap canister which contains the charcoal. Next time I will take it off (comes off easily) and wash it with water and a little dish soap rinsing it thoroughly with distilled water and drying it completely before reassembling. I think this will fix it just fine.

 

I just got the gascap signal and now the check engin light with a p0455 code. it's at the shop now. i changed the cap and no fix. so I'll see what they say. thanks for the insight.

 

What did the shop say the problem was?

 

I had the same problem with my jeep. It was fixed by simply replacing that module on vapor canister. A cheap fix for only $9.00.

 

DIY? How problematic was fix?

 

Took me one minute. all your do is disconnect the electrical sensor, twist the white piece clock wise, and remove the rubber tube from the white piece. The part number is 4891685-AB. it is called a detector. it cost me $9.05 at the dealership.

 

I just picked up the detector and a pcv valve! Hopefully these two items will fix the jeep!!!