Hey guys. I have a 2005 f-150 5.4L with 125K miles. At idle and usually much worse when it's in gear, my truck is experiencing what feels like an extremely random "miss". Sometimes it's worse than others, but overall it has gotten worse over the past few months. Under load, it seems to run just fine, and there's no CEL on nor are any codes being thrown. I did notice that under heavy acceleration there's a hint of rotten egg odor. Knowing that this can be a sign of bad catalytic converters and hearing that bad cats can cause rough idle, I had the cats checked today and sure enough they were bad. Had them replaced with Magnaflow hi-flow cats. Although the truck runs noticeably better now, the rough idle is still there, and there is still no CEL!!

I'm getting very frustrated with this problem, and I have no idea what to do or even where to start. Anybody experience this or know what might be going on?

FYI, the plugs and fuel filter were changed at about 90K miles.

Thanks in advance!

Jason

 

O2 sensors and MAF, plus a computer reset. Just guesses.

 

I'm betting you have leaky injectors. You have let it go too long, the extended warranty on them ran out at 120k. The warranty would have given you new converters too.

 

I didn't know anything about the extended warranty until yesterday when I was researching this. I'm not the original owner so I didn't get any notification of any kind. Wonder if Ford will work with me?

 

Leaky injector which fouled Catalytic and most likely front 02 sensor on that bank should be replaced as well.

 

He may be making a bomb. An 05, that motor could be history tomorrow, if the injectors aren't taken care off. That's risky deal right there.

 

Wow! Thanks for the gloom and doom, fellas! Think I'll just drive her off into the lake now.

 

I do not think it is that bad.

 

I guess I should have said, "Thanks jbrew". If what you said is all it is Norm, I'll be happy as long as it's just ONE injector.

I talked to Ford, and of course, they're not honoring the warranty. Said they never even sent out letters so I guess that's why I hadn't heard of it. Actually, one guy was a real jackass to me about it, and he got really smart when I asked him if Ford ever "bended" a little on such things. So, for $90 I'm going to take it to another Ford dealer and have them diagnose the problem. That way I'll at least know FOR SURE what's going on with it.

 

Don't jinx him Norm lol. Hate to see it Hydrolock on him. DewserB - This may happen in the 05 -

If she seems like she doesn't want to start, turns over slow, then locks, - DON'T force it. Pull the plugs, then whip it over.

 

Misfire on 4 and super nasty fuel system. $585 later she runs like new!

Oh, they checked the injectors and they're fine.

 

Right, - we will see..

 

Come to think of, I bet he got the updates. Or that was one real expensive fuel filter.

 

Sweet Lord, jbrew! Are you always this negative? If so, I don't see how you keep from jumping off a bridge or at least strangling kittens on a daily basis.

So let me get this straight. Of the over 939,000 F150s sold in 2005, every one of them is a ticking time-bomb waiting to explode? Really?

And since dealerships are notorious for suggesting MORE repairs be made than are necessary, and since I brought up the injector issue with the dealer, wouldn't it make sense that if there really was a problem with my injectors that they would have at least suggested they be changed? Heck, for that matter, if they were less than honest, wouldn't they suggest they be changed even if they WERE fine?

So you're implying that all the dealer did was replace the fuel filter an charged me $585? Really? That's odd because they must have handed me some other used coil pack and champion spark plug since I always request the parts that were replaced.

Please, go try and depress someone else. My truck is not doing what it was doing before, and it seems to be running better than ever.

 

I'm not saying the injectors won't stick, leak, ignite and cause an atomic explosion tomorrow. But for right now, she runs fine and according to the tech, the injectors were fine.