P0455,p0449,p0442 Codes

chvy1 · November 13, 2008

Does anyone know a solution to this problem? I have a 2006 Z71 5.3 V8 w/53,000 miles and every morning on my way to work I get a message "Tighten Gas Cap". The first two times I got this message I tightened the gas cap but it was already tight. Then my engine light came on and got these 3 codes (P0455,P0442,P0449). I called the dealer and they told me to replace the gas cap and this will solve my problem. Guess what it cleared up for a day. Now I still get the "Tighten Gas Cap" error in the morning and the code is P0455. I checked the lines and the purge valve. Everything looks good. I contacted the dealer again and they said for $300 they will drop the gas tank and change somekind of solenoid. I heard that there was a kit you can buy and this should solve the problem. Did anyone ever have this problem and can I change this myself to avoid the $300 dealer bill?

sledr · November 13, 2008

Read this......I posted this about a year ago.

http://www.gm-trucks.com/forums/index.php?...03&hl=sledr

This how I fixed my 442 code. It has been one year now and the "tighten gas cap" message has not returned

chvy1 · November 13, 2008

Does anyone know a solution to this problem? I have a 2006 Z71 5.3 V8 w/53,000 miles and every morning on my way to work I get a message "Tighten Gas Cap". The first two times I got this message I tightened the gas cap but it was already tight. Then my engine light came on and got these 3 codes (P0455,P0442,P0449). I called the dealer and they told me to replace the gas cap and this will solve my problem. Guess what it cleared up for a day. Now I still get the "Tighten Gas Cap" error in the morning and the code is P0455. I checked the lines and the purge valve. Everything looks good. I contacted the dealer again and they said for $300 they will drop the gas tank and change somekind of solenoid. I heard that there was a kit you can buy and this should solve the problem. Did anyone ever have this problem and can I change this myself to avoid the $300 dealer bill?

Do you think I need to re run the vent hose on top of the tranny?

slamed350 · November 14, 2008

tell the dealer u want a new vent valve solenoid, should cost around $110 installed

jGrenade · July 28, 2009

Does anyone know a solution to this problem? I have a 2006 Z71 5.3 V8 w/53,000 miles and every morning on my way to work I get a message "Tighten Gas Cap". The first two times I got this message I tightened the gas cap but it was already tight. Then my engine light came on and got these 3 codes (P0455,P0442,P0449). I called the dealer and they told me to replace the gas cap and this will solve my problem. Guess what it cleared up for a day. Now I still get the "Tighten Gas Cap" error in the morning and the code is P0455. I checked the lines and the purge valve. Everything looks good. I contacted the dealer again and they said for $300 they will drop the gas tank and change somekind of solenoid. I heard that there was a kit you can buy and this should solve the problem. Did anyone ever have this problem and can I change this myself to avoid the $300 dealer bill?

Do you think I need to re run the vent hose on top of the tranny?

I'm having the exact same problem, did you find a solution?

jGrenade · December 27, 2009

Does anyone know a solution to this problem? I have a 2006 Z71 5.3 V8 w/53,000 miles and every morning on my way to work I get a message "Tighten Gas Cap". The first two times I got this message I tightened the gas cap but it was already tight. Then my engine light came on and got these 3 codes (P0455,P0442,P0449). I called the dealer and they told me to replace the gas cap and this will solve my problem. Guess what it cleared up for a day. Now I still get the "Tighten Gas Cap" error in the morning and the code is P0455. I checked the lines and the purge valve. Everything looks good. I contacted the dealer again and they said for $300 they will drop the gas tank and change somekind of solenoid. I heard that there was a kit you can buy and this should solve the problem. Did anyone ever have this problem and can I change this myself to avoid the $300 dealer bill?

Do you think I need to re run the vent hose on top of the tranny?

I'm having the exact same problem, did you find a solution?

Ended up taking it to the dealer. They said the "evaporative e-valve" was burned up. Ended up costing me $900 bucks. Truck only had 36k miles.

Rudy35 · December 27, 2009

The dealerships are charging way too much. When I got the "tighten gas cap" code, it was the vent valve selonoid that was bad. GM wanted over a hundred bucks just in parts for the updated one so that the vent could be relocated above the transmission. I just went to RockAuto.com and bought the originial vent valve selonoid for $17. This fixed the code problem. My original valve lasted 5 years without the vent above the transmission, so for $17 I hope to get another 5 years. I also bought another $17 valve to have on the shelf for next time. Cheaper than what the dealership will charge!

desrtrat · December 28, 2009

Does anyone know a solution to this problem? I have a 2006 Z71 5.3 V8 w/53,000 miles and every morning on my way to work I get a message "Tighten Gas Cap". The first two times I got this message I tightened the gas cap but it was already tight. Then my engine light came on and got these 3 codes (P0455,P0442,P0449). I called the dealer and they told me to replace the gas cap and this will solve my problem. Guess what it cleared up for a day. Now I still get the "Tighten Gas Cap" error in the morning and the code is P0455. I checked the lines and the purge valve. Everything looks good. I contacted the dealer again and they said for $300 they will drop the gas tank and change somekind of solenoid. I heard that there was a kit you can buy and this should solve the problem. Did anyone ever have this problem and can I change this myself to avoid the $300 dealer bill?

Do you think I need to re run the vent hose on top of the tranny?

I'm having the exact same problem, did you find a solution?

Ended up taking it to the dealer. They said the "evaporative e-valve" was burned up. Ended up costing me $900 bucks. Truck only had 36k miles.

i may be wrong but, that should of been covered under FEDERAL emission warranty 7yr/70k mi..