They do in an '06 5.4, which was posted with 200K miles. Post #6.

 

Thanks I took it out of the housing, but didn't have the right tool with the hole in for the screws and didn't want to mess the screw heads up, so sprayed it with the inner housing still around it. I'll track down one of thse bits to take the screws out

 

if that doesnt work, ill sell you my sensor i took out of my 5.4 with 72K miles on it.

 

That's right! In the 06 models. The OP has an 03.

 

oh, and thanks for the info on the Bosch plugs - they were expensive, and I've used Bosch many times without problems, so thought I was doing the right thing:o I'll order some Motorcraft and see if there's a difference (at least I know how to change the plugs now!)

 

If you were losing power, one thing you might have checked is the cats. If thy are stopping up, that can cause a power loss.

 

I did wonder that, but assumed a check engine light would come on? I'll be taking it into an exhaust shop this week, as I have found a shop that has worked on other American trucks before, so I'll ask them.

If I've read correclty, I think I can have the rear cats removed? the shop did say they have removed all cats on some F150's - but I would have thought that would throw a fault code?!

 

Won't always throw a code, plus it may not be bad enough to throw one, yet you might notice it. I think you can remove the rears with no problem, the sensor is on the front. Cats may not be bad at all, but worth taking a look.

 

You won't usually get a DTC when the cats start to plug, -unfortunately. Either a vac test can be used to determine or restriction meter used by exhaust shops.

All 4 cats removed will cause efficiency DTC's. UNLESS these are programed out (via tuner). However, the economical way to beat this or if your needing new converters is to replace the 4 with 2 OX compliant units. Compliant, meaning, - two quality converters that fall within programed parameters (factory) on the efficiency scale.

Simply put , replace the 4 with two good ones. - IF need be.

 

Thanks jbrew, I know just enough about replacing cats to get in trouble! LOL

 

No problem. - If you do the work yourself, the money is a wash. Scrap yards are still paying that high dollar for used converters. Fords 4 converter set up brings close to $200 a set. Some yards pay you more, some less, but $200 was about average for along time.

 

Wow thanks for the imput I fogot how good this forum was, have learnt more of here in the last hour than weeks searching others! This'll make you laugh - I registered on here a couple of years ago, thought I'd been using it on and off, and it was another forum with a similar name:o I wondered why my log in details didn't work!

I've ordered a Supechips 1950 Cortex programmer, do you think something like that would allow me to program out the cats? Also, if it did show a fault code because of removing the cats, would if harm the engine, or effect the running? (I don't need cats here, but thought I'd have to keep them for the running of the truck)

 

No problem.

Well no, the programmer is just half of what you need. You would need custom tunes to go with.

Removing all cats with a factory tune, the truck would fall on it's face, drone like crazy and yes, it would not be good for the engine.