Error Code p0442

[hutch]

If anyone can help with this error code I would really appreciate it. I got a "Check Engine" light on my stock 2003 MM about three weeks ago. It came on when the fuel tank was about down to about 1/4 full. Last Friday I brought it to the dealer to have them check out the light. When I got my car back the invoice said they found the fault code to be "P0442." The comment said, "It's possible the gas cap may have been left loose after filling up causing evap leak, therefore causing chk engine light to come on." This is after I told them that it didn't come on right after refueling. Unfortunately I brought the car in after filling up the gas tank and the dealer said that if it comes on again to bring it back with qtr to half a tank of gas in it. Yesterday while I was driving my fuel gauge got to 1/4 tank the "Check Engine" light came back on. I have to bring it back to the dealer but I would like to know if any of you have any ideas of what might be the cause. Thanks!
Eric Hutch

[Bradley G]

I looked in my SCT book this code says:evap emission system leak dected (small leak)hope this helps:cool:

[SergntMac]

The check engine MIL will come on when the gas cap is off, loose, or leaking. Once you reseal it, the MIL should go away in a short periord of time, 4-5 cycles of the ignition key should clear it.

[MAD-3R]

If anyone can help with this error code I would really appreciate it. I got a "Check Engine" light on my stock 2003 MM about three weeks ago. It came on when the fuel tank was about down to about 1/4 full. Last Friday I brought it to the dealer to have them check out the light. When I got my car back the invoice said they found the fault code to be "P0442." The comment said, "It's possible the gas cap may have been left loose after filling up causing evap leak, therefore causing chk engine light to come on." This is after I told them that it didn't come on right after refueling. Unfortunately I brought the car in after filling up the gas tank and the dealer said that if it comes on again to bring it back with qtr to half a tank of gas in it. Yesterday while I was driving my fuel gauge got to 1/4 tank the "Check Engine" light came back on. I have to bring it back to the dealer but I would like to know if any of you have any ideas of what might be the cause. Thanks!
Eric Hutch



Do you top off your tank to the max? bump the sides of your car to squeeeze the last quarter gallon in?

If so, then liquid fual may have gotten into the vapor return line.

http://www.patgosscarworld.com/donttop.htm

[Bradley G]

Wow Thanks MAD-3R, I am(was) a topper offer I do this to keep trac of mileage. I had no Idea I was doing potential harm. this info is much appreciated!Repeat after me " I will not be a Topper Offer"Hey that's not too bad:woohoo:

[hutch]

Thanks for all the replies, this is why I love this site! To answer MAD-3r, I don't top off but I do sometimes "squeeze" the last little bit out of the gas nozzle (gas is expensive here in CA). I'll keep everyone's idea in mind when I bring it back to the dealer to get it repaired.

Eric Hutch

[Krytin]

My wife has done this more than once! The check engine light does not come on right away when you leave the cap loose! It takes one or two "cycles" for the "leak" to be picked up by the computer! I top off the tank all the time and have never got a check engine light. It's amazing how much these cooomputers can do on cars today!

[Bluerauder]

Do you top off your tank to the max? bump the sides of your car to squeeeze the last quarter gallon in?

If so, then liquid fual may have gotten into the vapor return line.

http://www.patgosscarworld.com/donttop.htm
Excellent information, Phil. Thanks. :up: