Figured out my P0442 code. I think...

[timmer]

As most of you probably know a while back my KJ's Check Engine light came on and I was very excited because I had an excuse to buy a scan tool.

Anyway, I've been monitoring this code for about a month or so to see if I could detect any pattern to it. I did, but it was subtle.

First off I should say that I discounted the gas cap right away; I always tighten it and I never forget to put it on.

So, I cleared the code and about every tank full of gas I would get it back but only while driving on city streets. I drive a lot of long distances and not once did it throw a code at highway speeds. Also, last week I got a P0445 code with the P0442; that told me something was deteriorating.

Hmmm, I did a Google on the code but there's not really any solution to the code on the net. There was several references to the Vapor Canister though and I started there.

After about 1 minute under the Jeep I found a dry-rotted and cracked piece of hose to the Vapor Canister that mates to the Fuel Vapor Line.

I replaced that hose and I have yet to throw a code again after two tanks of gas.

Fixed?

We'll see, but here a pic of the hose:

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For those of you that don't know, I have an 02 Limited so your setup may be different. The pic came from my 02 manual and the P/N of this hose is 53013091AF - TUBE, Fuel Vapor.

 

[Dave]

Looks similar to my 05, but I havn't been under mine since the last oil change so I'm not positive.

Glad you got it fixed.

Dave

 

[JeepJeepster]

My 04's evap system looks the same.

Im OCD about coating things in silicone spray, so I always give those tubes a good wipe down in silicone to try and prevent that.

 

[tjkj2002]

Yep,had the same thing,that darn line had a small crack in it and was not visiable due to all the undercoating,some 3/8" fule line fixed it real fast.Just remember 99% of all evap codes are from leaks and about 75% of those leaks are from the gas cap.

 

[timmer]

My 04's evap system looks the same.

Im OCD about coating things in silicone spray, so I always give those tubes a good wipe down in silicone to try and prevent that.

Would that by any chance be a McGuires Silicone product?

 

[Dave]

Would that by any chance be a McGuires Silicone product?

"Maguires Evap and Breast Implant Spray"..........black and maroon bottle

Dave

 

[JeepJeepster]

hahahaha. Man I tell ya, you all are on a roll!

I have a CRC silicone spray but it *****. Its basically CO2 that evaporates after I spray it on something..

I have another spray that I really like and I cannot for the life of me remember the name of. It has a yellow cap and I can only find it at autozone.. Ive been needing to pick another can up.. It really seems to go along way.. I spray just about everything there is to spray thats rubber under the jeeps and its lasted over a year. I try to do it at every oil change..

 

[icarl]

I had the same problem (P0442) last week on my 02 liberty and read on the forums about the cracked hose issue. Sure enough, my hose was cracked as well. I replaced it and have yet to see the engine light since.

 

[joeg]

Brake fluid

...Just wipe down with a rag with brake fluid. It's job is to keep brake seals soft and pliable and it does well on any rubber hose..............Used it often for years..

 

[libertyman]

WOW thanks that was the problem with my 03 liberty.

 

[timmer]

Hi Folks!

Just got the P0442 code again so when I get a minute or two, when its dry, and I have enough light, and not too cold, I'm going to check that hose again.

The Jeep now has 178,000 + miles on it and is still running strong.

Haven't been on here for a while because I got a motorcycle in June and have been playing with that. Also, I finally got my profile filled out so I can see the threads! Is Bennett in Tahiti?

Here the picture that won't show up above, the hose I replaced - I reorganized my Photobucket so the link is dead.

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[timmer]

I hope I figured this out again. I found a broken clamp (plastic) right next to the line I replaced before, marked in red.

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I put a couple of cable ties on it for the time being and cinched them down tight. If I don't get the code again in a couple of days I'll put a proper clamp on there.

 

[bmrrwolfe]

Thanks for the diagram, my sisters KJ just got a P0442 code also so I will need to crawl underneath and see if I can find any rotted hoses!

 

[brendanc]

Got code P0442. I checked the gas cap and it doesn't seem to be that. I always tighten it several clicks as well.

I crawled under the rear end and inspected the hoses coming off of the vapor canister. They seemed fine but I took the hoses off anyway and pulled out the vapor canister to inspect it. I was going to replace the fuel vapor tube as the OP listed, but:

1. Jeep wants $65 for the rubber hose
2. a standard 3/8" hose won't fit over the vapor canister end because the size is more like 7/16" or 1/2" (ID).

So I'm going to inspect it, rub it down with some silicon grease and put it back on. I'm thinking the leak is somewhere else. I checked the clips on the other two hoses coming out of the vapor canister and one of the clips was slightly loose (not broken, though) so maybe that was it and I just overlooked it.

I can't believe Jeep would try to charge $65 for a freaking 6" piece of rubber. I looked on amazon at some silicon rubber tubing. Looked like it would stretch more easily than the rubber i picked up at track auto-- does anyone know if this would suffice, just in case I end up needing to replace it? Or do you think the tube would collapse under vacuum pressure?

 

[jnaut]

I'd give you odds that you did fix it.

 

[brendanc]

Cleared the code, didn't come back right away after reattaching all hoses and re-tightening the ratchet clips. Don't settle for finger tight on these clips. Use a pair of vice grips (set semi-loosely) and go one click past what you can get without making your fingers hurt. The clips should be in place really solid and won't be able to rotate around the hoses (like one of mine was).

Will update if it comes back.

 

[mikeandamy]

should there be clamps on all 3 hose connections on the canister? i have a p0442 code and when i looked underneath there are no clamps on any of the connections.

 

[norm6269]

Cleared the code, didn't come back right away after reattaching all hoses and re-tightening the ratchet clips. Don't settle for finger tight on these clips. Use a pair of vice grips (set semi-loosely) and go one click past what you can get without making your fingers hurt. The clips should be in place really solid and won't be able to rotate around the hoses (like one of mine was).

Will update if it comes back.

Did you buy OEM hose? I ditto your hesitation on buying $65 rubber hose. If you didnt buy the OE hose which size did you buy, thanks.