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engine code P0454 possible fixes

KTB

New Member
Messages
3
Likes
0
Location
San Angelo, TX, USA
#1
I had check engine light and code P0454 (Evaporative Emission System Pressure Sensor / Switch Intermittent) pop up while commuting a week ago. Cleared it, and it has not come back since, but idle stumble and longer cranking at startup. From what I've read, the possible fixes are the evap purge valve under the hood (Motorcraft part # CX2456) or purge valve on the charcoal canister in the rear (Ford part # CU5Z-9F945-A). Has anyone fixed the issue with one or both of the evap purge valves?

Since the underhood evap purge valve "harness" with tubing (F2BZ9C047C (2016+) or D2BZ9C047F (2014-15)) is on perpetual backorder, has anyone had luck replacing the purge valve only, and reconnecting tubing with 3/8" fuel hose and clamps like FiestaSTdude's image below?

F3CC70ED-09F9-4A7A-A379-A51437EE93E4.jpeg
 


Sam4

Senior Member
Messages
952
Likes
717
Location
West Chester, PA, USA
#2
Going to find out soon - I have the valve, but have always replace the assy. This is the first time I've actually thrown the code (420), I replaced due to the fillup hiccup. I'll post when I do it.
 


Messages
13
Likes
7
Location
Nashville
#3
I had the other code for evap unable to bleed up vacuum or something. Replaced purge and now have p0454.

My non mechanic guess is that the charcoal canister sensor thing went out first and confused the computer into thinking it needs to purge more often, which burn out or wear out the purge valve in the engine bay.

I'll get a new sensor ordered up and will forget to update this post if it fixes it.
 


Sam4

Senior Member
Messages
952
Likes
717
Location
West Chester, PA, USA
#4
I'm messing with the check valve in the rear to/from the charcoal box. and figuring I've replaced the front one w/o need...
 




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