Hi all,
I hope someone can help me out. Like the title says, I have an 05 F250 with the 5.4l. The other day, after I had to accelerate hard to cross a highway (right lane on ramp to far left lane in a few hundred feet) my check engine light came on. Didn't think too much of it at the time, as everything was fine, and I figured it had to do with the acceleration. Had my trailer loaded, so there was an extra 3500 lbs, but that's no sweat for a 250.
this morning, as I began my 30 min drive to work, I noticed that, under moderate to hard acceleration, the CEL would blink, and I have what felt like half the power. The light would go back to steady burn a few seconds after I let off the gas.
It idles fine, and I don't hear anything wrong with the engine (tick, etc) so I doubt it's internal. I did hear what I can only describe as a backfire from under the hood, but that was only once, after it upshifted.

Any idea what this could be? I haven't scanned the code yet, gotta find a friend who has an OBD-2 scanner.

the truck has roughly 201,000 miles on it, and is stock except for a K&N intake put on by a previous owner.
Thanks in advance.

 

 

Thanks. That also might explain why I'm only getting 9mpg....
Would getting a high flow cat be worth it? I plan on keeping this truck awhile.
There was someone on here who sold high flow cats, and the company name was "mountain" or something like that. Anyone know if he's still around? I'd like to buy from him if possible.