I have a 2007 ford f150 xlt 4x4 5.4L vin 1FTPX145X7NA05418 that I bought at an auction with an engine code showing. the code did not affect the operation of the vehicle until a couple months later. then it quit and I had the motor changed with a crate remanufactured motor from a company in florida , supposedly they had an issue with oil porting being to small. Afterward, it plugged the catalytic convertor and I took it in and it was changed along with the spark plugs. with in a month it had plugged again. took it back and the did the same, changed the cat and plugs. a month later it did it again so this time I took it to a Ford Dealer and the did the same thing. changed the cat and plugs. a month later same issue. each time there were codes for different cylinders misfiring. it was taken to another garage and they wanted to do the same thing but I was tired of dumping money for the same thing to not be remedied so I just parked the truck. fast forward a couple years, I would like to try get it working. Does anyone have any suggestions. The last time, I did remove the cat convertor. I am thinking maybe the Electronic Control Module may be faulty????

 

CATS dont fail on their own... either there was nothing wrong with the CAT ( some other problem)... Or you have bad injectors and it was flooding the exhaust and killing the CAT..... Either way there should be CODES that were telling you the problem.

 

Right? Cat converters don’t just spontaneously melt down.

Sounds like OP got himself an auction castoff that needed an inevitable timing job and thought the computer was pushing out codes as a joke.

Don’t overthink this, OP. 3V 5.4 engines have a track record and bad computers aren’t generally part of that.

If you need to source a quality remanned engine, there are folks that can get you headed in the right direction. Otherwise, you’re pretty skimpy on details here.

 

I dont have access to the codes as the truck has been sitting for a couple years now, but they were rotating between 4 cylinders saying coil pack or cyl misfire as my memory goes. I would have thought the Ford garage would have figured it out but they only did what the others had already done

 

NEVER assume a shop knows what they are doing.
Assume they don't until proven otherwise.
As the others said, you don't just foul a converter without cause.
Not to mention, it should have been REALLY obvious something is not running right prior to destroying multiple converters.

Code scanners are not terribly expensive & when it was running, any major auto parts store would have scanned it for you for free to let you know what codes are there.

 

Almost every car has it's own specific nuances. That is why some shops specialize. It's always better to find a shop which specializes in Fords. They are out there. Often operated by people who were once dealership techs who have a lot of Ford experience.


Wherever you are in the world, I would suggest taking your time and trying to find the right shop for your truck. A lot of shops are "general" mechanics, and don't really specialize in anything. I have a neighbor like that. His shop does body work, brakes, oil changes, and things like that. He has a wide breadth of knowledge. But no in-depth knowledge on any car. He may know a little more about Hondas and Toyotas, because more of them come to his shop. He may know less about Audi & VW. Sometimes, he is wrong. All cars are a little different.