A few months back I posted here a light hearted recap of a spark plug change on my 2006 F-150 5.4 Triton with 78K on it. Something Ford wanted to charge me $750 to do. It was PITA, took all weekend, but it was accomplished. It should have never had to have been done in that manner but I was making light of a crappy design in that post. 1,000 miles and running great. Until 2 weeks ago.
I was starting to pick up a miss, with no CEL. My OBD II reader showed it as a No. 8 random miss fire. So my logical thought based on the fail rates experienced was a coil pack. No problem. Tomorrow I will swap them and make sure the problem moves. Pretty easy job all in all. So the next morning I do that. Go to start the engine and the engine gives me a quarter second of movement, kicks a click and then kicks back slightly. Then nothing. Felt like a dead battery. Which was odd because I has just replaced it about 8 months ago. So I just figured, cold snap, bad battery, a bad luck event.
Pull the battery, checks good at battery shop. Hmmmmm. Must be a bad connection I guess. Cleaned everything and put it back together. Started it up to hear a distinct and obvious but light knock now. WTH. Shut it down, searched for anything obvious. Nothing. Had it towed to a shop. A week into the repairs. Get a call...."You need to come down here and see this". That never gives you a sense of comfort. Go down to the shop. Front engine torn down, pan is off. "Look up at No. 8 piston. See that shiny spot?" Yes. "OK now look here on the crank, see that rub spot there?" Yes. The bottom of the piston is kissing the crank counterweight right there. I can't deny what I am looking at. OK so what caused that. We ponder it a bit. I said, look the only way that can happen is for the distance between the two to be wrong. Mechanically these things don't just touch for no reason. The piston must be bad or something. Which doesn't make sense but we have what we have.
Ok guys pull it down, lets see what we got. They called me back and said Come see again. So the head was now off. No interference between valves and piston took place. "What do you want us to do next?" Go ahead and pull the piston and rod out. Something isn't right somewhere. I stay there to observe. Pulled No. 8 Rod/Piston and it was clearly a bent rod. What in the PHU**** is going on here!!! Pull up the internet research. Googled in 2006 F-150 bent rods and Bingo, lots of them. Even more in 2005 and some in 2004. Turns out Ford recalled the entire 2005 year of this engine because of faulty Fuel Injectors sticking open. Actually it wasn't a recall, it was deemed a customer satisfaction program. Checked the affected vehicles. Mine was produced one week after the last VIN ID was specified.
Called Ford. Sorry not covered. Yours is a 2006 and not affected. Great news!!! Researched affected Fuel Injectors. List the part numbers, and lot numbers of these fuel injectors. Research that and found that in late 2004, all through 2005 and early 2006 they used the same source vendor and same lot number sequencing from the tail end of 2004 through early 2006. Then they changed sources. Yet Ford only recalled the 2005 model year since that was in the 10s of thousands affected vs the few thousand of 2004 and 2006 years. For the 2005 Model year recall, they are warranted against this for 112K miles or 11 years whichever comes first. Including engine replacement if damage occurred. Called Ford again. Explained all of that. Was told to pound sand.
Here is the failure mode of these injectors. They fail to the open position, at first they just stay open longer than they should but eventually just fail and are in the open position only. So, if we turn off the engine, and the injector is failed open, it will drain the fuel line full of fuel (under pressure) down into that intake path. In this case No. 8. So this is about 50CCs of liquid in total. If when you stop the engine the intake valve is closed, that fuel stays blocked behind the valve in the intake run of the manifold and head. The next time you start it, the piston will travel down on the intake stroke, filling the cylinder. The valves will both be closed entering into compression stroke. The piston will then travel up as normal and be unable to compress the liquid which is now trapped in the cylinder with no place to go. The starter, does its best, and forces that piston into an im-moveble mass of liquid with enough force that the rod gets bent. Also known as Hyrdo Lock.
No longer a lighthearted mood here. See ya in court Ford.