Good afternoon.

This is my first post, so please be patient with me.

2005 Crew F-150 5.4L 47,000 Miles
A couple of months ago an injector stuck open. The dealer replaced the injector under warrantly. I also let the dealer reprogram the ECU and clean the fuel system, per there recommendation.

3000 miles later the engine starts cutting out at 4000 RPM, lots of popping and preignition rattle, and the engine light flashes and then glows steady. Also, the intake noise was a lot louder than usual.

The dealer said that the engine code indicated a missfire, not specific to any cylinder. They replaced 8 plugs with new design, one plug broke. The charge for this service was $275.00.

The dealer tells me that the Cat is plugged up and they will replace it under the emissions warranty.

Also, they claim that the timing chain tensioners need to be replaced for approximately $1500.

It seems odd to me that at 47,000 miles, mostly highway miles commuting 75 miles a day, that any internal engine work would be required.

What is the groups experience with chain tensioners on a 2005, 5.4L engine?

 

What about the 5 year/ 60,000 mile powertrain warranty? The timing chain tensioner
is in the engine. It's the first part of the powertrain. Maybe you need to consult another service department.

 

^I don't think he has the 5yr/60k powertrain warranty for his 2005, I think Ford first started offering that in 2006.

 

Correct, Ford did not start the 5yr/60k until July 06

 

I found out that the codes were for a mis-fire on #5 and random mis-fires.

#5 cylinder is the one that had the broken spark plug.

What would cause a random mis-fire?

The engine is clean and dry around the plugs.

 

Coil Pack?

 

Another injector on its way to sticking open?

 

The Dealership (Coastal) did a great job and got my truck running right.
They replaced the Cats and it runs great. The Cats were replaced under the emissions warranty ($1500). Also, the chain tensioners are OK. The reason the cats failed is not known for sure, but I suspect that when the Injector stuck in the open position, 3000 miles ago, raw gas was going through the exhaust. My hats off for the tech who worked on my truck and the Service Writer who kept me up to date.

Scott