Drive Cycle Won't Complete

5HITBOX · January 8

So I've had a few codes pop up on my truck for the EVAP system. Initially it was P0446 and upon being cleared, was replaced with P0451. After my repair, I attempted to have it cycle through, however, the drive cycle will not repeated as the P0451 code is still set as pending.

Miles driven since clearing the light: 351.

swathdiver · January 9

You could have a bad sensor but more than likely you have an obstruction in the line that needs to be cleared. Probably charcoal pellets.

redvett · January 10

How do I fix error code P0451?

What repairs can fix the P0451 code?

Repairing or replacing the gas tank.
Repairing or replacing a faulty fuel tank pressure sensor.
Replacing defective or damaged wiring or connectors in the fuel tank pressure sensor circuit.
Replacing the canister vent valve.
Replacing or reprogramming the PCM (rare).

newdude · January 10

On 1/7/2023 at 11:01 PM, 5HITBOX said:

So I've had a few codes pop up on my truck for the EVAP system. Initially it was P0446 and upon being cleared, was replaced with P0451. After my repair, I attempted to have it cycle through, however, the drive cycle will not repeated as the P0451 code is still set as pending.

Miles driven since clearing the light: 351.

Got some more info on the truck? Year? Make? Model? P0451 is tank pressure I think, but need the details on what you drive.

Are you trying to get a sticker on it then worry about fixing it?

If so, try filling the tank full then clear the codes and re-drive cycle it. See if you can get all of the others to set except for EVAP. If there are say 8 monitors total, 7 of them need to be set for emissions inspection.

Edited January 10 by newdude