2012 SIERRA 5.3L, CODE "P0451".

[Bad Bowtie2]

Twice this week I have emissions code "P0451" display, then reset while driving. Seems to be a very vague code, not really saying what is wrong. Just that the PCM has ran an emissions system test & something failed. Could be low voltage, bad connection, failing vacuum pressure valve, and/or pinched or leaking vacuum line.

 

My truck is all stock, less me installing The Range module well over a year ago. I tried driving my truck with & without the Range installed, just to eliminate that as setting a faulty code. This does not appear to be the source of my problem.

 

Just thought I'd see if anyone else's 2007.5-2013 5.3L has had this problem on here. The "search" function only pulled a similar trouble case on a guy's 2006 Silverado, back in 2011.

 

Thanks in advance guys/gals...

-Jon in TX.

[newdude]

P0451 is Fuel Tank Pressure (FTP) Sensor Performance (so not exactly a vague code, rather specific). Common part to fail just like the vent valves on the GMT-900 trucks.

[Bad Bowtie2]

Well, I've already got one ordered. Just wonder if anyone else might have had an actual EVAP hose leak or the "other" in-line fuel pressure sensor fail (located between the tank and engine)...

 

I'm going to add a tab of dielectric grease to these wiring connectors too, while I'm under there....