05F150XLT

I just posted a couple days ago about having a misfire in cylinder 8, well I replaced the coil and reset the computer. Now my 05 XLT 5.4 shudders, but it does it randomly, it almost the same thing it did the first time when the CEL came on, indicating the misfire, but it had stayed off since I reset the computer. Then only time it does this shudder is between 3000 and 4000 RPM, and when it shudders I have no power and the RPMs don't rise, and only when I'm giving it more then half throttle. Like I said it does this randomly.
Any ideas?
Thanks in advance guys.

primalurges

You may have another bad coil. Is the CEL blinking when you are experiencing the misfire? If it is you'll receive another code when it gets bad enough. I've only had one coil go bad in my truck at 50K, but have heard of other members experiencing more than one failure within a few months of each other.

05F150XLT

See that's the thing the CEL isn't blinking this time, that's what's throwing me off. So I'm not sure if it's another misfire.

primalurges

When I had the problem it took about a month for the CEL to turn on. Initially it was very momentary 2 or 3 seconds a couple of times during my 40 mile commute usually at around 50mph and didn't feel like a misfire until it became much worse. What I did to hurry up the code once the problem got worse was I'd disengage overdrive at highway speeds and would gun it, causing the engine to misfire quite a bit. If that doesn't work you're just going to have to wait it out.

05F150XLT

Ok thanks. I just hope that it doesn't give me too much trouble. I have a long trip tomorrow. I PCS to Moody AFB from Louisville, KY. So i hope that it gives me its best.