Hey fellas. First time in this forum. Just picked up an 05 expedition xlt with 153k on it. It had some phaser and coil issues when the PO got it so he recently installed new vct solenoids, full timing kit (some Amazon kit, not oem but not dorman parts), 7 coils (gave me the other but just didn't want to put #4 on), new battery, newer tires, and a sway bar link. Said he could see the passenger head had been replaced because everything up there was new along with the timing chain and related parts on that side. Got a decent deal @ 2900 bucks.

There are a couple things of note though. The temp control is not working. I get cold air only when @ max A/C, all other positions act like full heat. Done a little research and I think this a symptom of a dead door blend actuator? If someone could help me confirm that would be great. I've seen the video of how to replace and it seems easy enough. Doesn't make any clicking/clunking sounds though so thought I'd double check.

It's also a little noisy on startup for about 10-15sec but smooths out and seems to run fine. Good power, shifts smooth. I drove it about 100miles home down I35. When I finally came to a stop sign it kind of shuddered a bit, but accelerated fine and afterwards seemed ok. Any cause for concern there?

Sorry for the book but I don't drive much new stuff and don't have any experience with a 5.4l so thought I'd let our resident experts steer me.

 

Hey Sleepy this is Slayjr. I believe that blen door is what controls the system from transferring from hot to cold. Mine was clicking but eventually stop and stayed in the heat position in the middle of summer!😂😂 So go figure! But yes, I would start there! Hope it helps!

 

Thank you! I thought so but just wanted to double check since it wasn't making the usual clunk people describe. Be picking one up or ordering it this week and putting it in asap! At least the max a.c. still blows cold so I'm not suffering too bad in the meantime

 

The blend doors are a common failure on these. Sometimes you get vehicles where the PO simply unplugged the actuator to stop the clicking, so might want to check that out. Unfortunately, these parts continue to fail, I replaced one on the rear AC and it lasted about a year, it was the duct actuator for roof/floor, so I simply locked it on roof and unplugged it since I never use it on floor anyway.

As for running rough on startup. How rough exactly? Mine is slightly louder at startup but settles after a few seconds. I suppose that's normal and part of the startup sequence where the PCM starts receiving signals from a running engine and adjusts timing and ratios accordingly. But if it's getting really rough, as a misfire or something else, then that will have to be diagnosed.

 

It's just kind of clattery when cold. Valvetrain is noisy but after about 15 seconds it smooths up and then seems quiet and smooth. I'll try to get a video soon so y'all can hear if it's normal noises for a 5.4. There's no codes or anything

 

@ Sleepy; Gm, my 2006 Expo is doing the same thing. I took it to a Muffler shop yesterday evening and he couldn't find a leak. I turned the truck off while we inspected under the truck. Mind you, it was pretty cold outside. When I got ready to leave i started the truck and it made that clattery noise and he said, that is your Exhust manifold gasket. So I'm guessing thats why I'm smelling all off these fumes in the cabin and hearing that God awful noise at start up. Let me know how you made out!!