P0455 P0442 evap evaporative emissions leak fix
A little info like all of it, about your truck added to your sig and profile might be helpful.
sorry I have a 01 ram sport 360. the shop smoke tested it and replaced one part under the hood said it was bad reset everything for inspection 2 days later light came back on so took it back. they smoke tested again and said the second piece under the hood had to be replaced so replaced that. day and a half later light on again both times it said a large evap leak. smoke tested the fuel tank with no leak and retested whole system from under hood again with no leak. dodge place said if exhaust was unhooked before converter would make it say large leak that was all good when checked. they reset check engine light 2 days later light come back on but was weekend so just drove it. on monday light went out so took it up they put computer back on it but it said the O2 sensor and the evap had still not reset. so i guess where do i go from here? also said they had never had one that took so long for everything to reset.
Last edited by BCredram; May 23, 2012 at 11:39 AM.
i asked which sensor but they could not tell me never found any leaks in the lines. I took it back up today because the light was still out and everything checked out fine with it and it passed inspection. maybe it just don't like me or somethin!!
I'll tell you how the evap system works so you can better trouble shoot. A large leak is generally a bad gas cap,but not always.
The Evap system is for vapor recovery,but the system check is done by the computer by acctually pressurizing the gas tank to 1psi. This first checks to see if there are any leaks,hence the gas cap being bad won't hold the pressure if the check valve is bad.
The way the computer knows if there is a leak or not is by counting the number of pump pulses it takes to pressurize the tank at a given fuel level off of the fuel level sender. A bad fuel level sender or one that reads incorrectly at a couple spots will cause a leak code also
i got this info from an older post, i have checked all the lines so i guess i will go ahead and replace the pump because i have been living with a flakey gauge for some time
The Evap system is for vapor recovery,but the system check is done by the computer by acctually pressurizing the gas tank to 1psi. This first checks to see if there are any leaks,hence the gas cap being bad won't hold the pressure if the check valve is bad.
The way the computer knows if there is a leak or not is by counting the number of pump pulses it takes to pressurize the tank at a given fuel level off of the fuel level sender. A bad fuel level sender or one that reads incorrectly at a couple spots will cause a leak code also
i got this info from an older post, i have checked all the lines so i guess i will go ahead and replace the pump because i have been living with a flakey gauge for some time







