2005 Excursion P0404 and P1335

mchan68 · September 24, 2015

Hi guys. I have a 2005 Excursion equipped with a 2004 engine in it (with an EGR throttle plate) that set the DTCs P0404 and P1335. EGR_VP indicated 1.38 volts at KOEO so I slammed a new EGR valve at it (part number CX-2466-RM for 2005 and up engines as is listed for this particular truck in Microcat). Vehicle has now returned a week later with the exact same DTCs, and yet again EGR_VP indicates 1.38 or so volts at KOEO. Is there any possibility I installed the incorrect EGR valve, since it has a 2004 engine in it, even though it lists the 2005 and newer part number for this vehicle? I know there are a lot of 2005 Excursions out there that came from the factory with 2004 engines in them. For clarity, this particular truck's build date is 23-JULY-2004.

Keith Browning · September 25, 2015

I would think that if the valve was the problem it would have been evident on your post repair testing and road test... No? The voltage of the closed valve indicates a circuit issue or more likely a debris. Did you pull the valve and inspect it? On several occasions I have has residual debris get caught in EGR valves. If this is the case, remove the debris and look at it closely by crushing it and noting if the carbon is soft or hardened with a gray appearance...

If there is debris and it is black and soft, start the engine with the valve out and rev the engine hard several times to blow out loose carbon from the cooler and manifold EGR passage. If the carbon is light gray and hard replace the EGR COOLER.

Matt Saunoras · September 25, 2015

I would think even though it is an 05 MY since it's definitely an 04 engine, verified by the throttle plate, that it would use 04 programming also.

I have no idea what the differences are with the valves but I do believe there must actually be a difference. The outer appearance is the same so it must be with the electronics.

If you would like I'll take an 03-04 valve and plug it into an 05 truck and see if it faults or reads different KOEO

mchan68 · September 25, 2015

It's okay. Hotline confirmed that I should have installed a valve for an '04 engine, even though Microcat lists a valve for an '05 engine for THIS '05 Excursion. Apparently on Excursions, '05 engines weren't installed until January of 2005 build and onwards. So, if any of you guys ever come across an '05 Excursion with an '04 engine, use '04 engine parts.