03 expy 5.4 runs like crap

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cahess

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Well... thanks to all the members and posts of this site, I had an issue and I was able to find the solution and fix the problem, however, I need some more suggestions.

Engine was running very rough, crappy, and finally (so I could learn what was wrong) the check engine light came on... flashing at first, then finally just stayed on. When to the auto store, read the codes and found that I had a misfire in cylinder 7. replaced the coil and since I have 80,000 miles, changed he plugs too. Went with autolites (double platnum I thinik) Runs much better, that was definantly the problem. Since I changed the plugs and the coil on number 7, I thought I should just go agead and do a full tune-up. I bought a new pcv valve, fuel filter, cleaned my air filter (K&N - but not a cold air intake kit), and bought a couple cans of sea foam (which I will do all but the oil since I just had an oil change... I'll wait a month, do the crank case then, and drive to the dealership for an oil change) Also cleaned the MAF with MAF cleaner. (spray) What else should I do that would normall get done at the 100,000 mile reccommended tune-up. Or what do you all reccommend to get done. Thanks for the advice. Oh, just did a tranny flush and will go ahead and get the radiator flushed as well. Noticed the fluid is a greeen-brown so I'm sure its due.

Should mention the truck is running great now, I'm just looking to do any preventative maintenance that I should, so I dodn't have to worry about it for a while (I hope)
 
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mustangrfast88

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autolite makes a good plug but i would of stayed with motorcraft since that is what the engine was researched and devoloped with i have since changing plug make a differance in milage and performance in a short amount of time but it was with cheap spark plugs
 
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cahess

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I have seen several people post in here that bosch were crap (the auto parts guy wouldn't even sell me bosch, told me the autolites were what was reccommended for the ford 4.6 or 5.4) and that people on this site were very happy with the autolites. I hope they work well, they sure wern't cheap at 4.00 each.
 

pronstar

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I advocate replacing the upstream O2 sensors at regular intervals (40K miles or so), though many will suggest waiting until they throw a code.

$4 a pop isn't bad.
The AutoLite HT0s that I use run almost $20 each.
 
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