TBC

FIXED! SEE POST # 18






MY truck is an '04 F150 FX4 SC 5.4 Triton. Issue started yesterday about 3 blocks from home. Started up fine and ran great until I stopped at a light, as I came to a stop it was shuttering and barely running, did not take the gas well so I limped back home and parked it, no CEL on dash or with my code reader. Started it today with same issues, starts right up but barely idles and wants to die. If I give it throttle it almost dies (tach drops) but if I rev it to about 2500-3000 rpm it smoothes out somewhat for a few seconds, will idle fair then go back to barely running. After doing that I got 2 codes, p2195 and p2198 (bank 1 lean and bank 2 rich). Ran it up one more time and now there are 5 codes, the original p2195, p2198 plus now it has p0300 (multiple misfires), p0356 (ignition coil), and another p2198. I replaced the plugs with Champions 2000 miles ago along with and oil change, motorcraft oil filter and Bosch COPs along with a new air filter. Ran great until I came to that stop yesterday about 2 minutes into the trip.
Any ideas on which direction to start looking would be appreciated. What's got me puzzled is one lean bank and one rich bank. Misfires are probably from the rich or lean condition I'd assume. Truck has no mods and never has.

sigmanf150

Air filter restricted? Have you cleaned the MAF or cleaned the carbon on the throttle body? Check for vacuum leaks around the intake area.

TBC

Air filter is new (2000 miles ago) and I cleaned the MAF before I changed the plugs. Have not cleaned the TB yet. Looked and listened for a vacuum leak but I have not used the carb cleaner method to see if it affects the idle, the weather is getting bad here and I cannot get it inside. Just very strange how quick it came on plus the lean and rich condition simultaneously. First time this year I need a 4x4 and it decides to go down for the count...Ug.

JimmyB1232

I've heard the Champion plugs can/will fail very quickly and the 3 Bosch COPs I had in went bad within a month. I somehow fouled up all 8 Motorcraft plugs after 3-3,500k miles last year. I've been told by a few mechanic buddies of mine that these motors will run rich in cold weather and even more so if you're constantly letting the truck sit and idle for extended periods of time to warm up. And when you're running rich that's when you start clogging up the CATS. Apparently that's how I fouled up my plugs so quickly. Have you pulled the COPs out and make sure none of the plugs have busted? And does your scanner have Livedata?

TBC

I'm going to pull the plugs to check for fouling when I can get it to my shop indoors. Have my old COPs so I can try them too. This went from running perfect to barely running in a matter of seconds though. If plugs and coils were going I'd think it would be gradual or at least have a smaller misfire to start with. I'm wondering about a stuck injector or possible cam timing issue (phaser/VCT solenoid). No cam codes yet though. My pocket scanner does have livedata but not sure what to look for.

j.low

Been there with rough idling and found my Cats were worn out. (213,000miles)
replaced Cats and O2's ($$$$) and it runs like new. Cats are weird animals and apparently send varying fuel flow signals to the computer if the Cats are plugging.
I put nothing but gas in the tank.
Good luck

sigmanf150

I've got 305k on my stock Cats.

mattcline8

My cats went bad at 105k... It sounds like that to me...

techrep

iTrader: (1)

Plugs need to be swapped out for Motorcraft...and COP's need to be swapped out for Motorcraft or Accel ..our trucks are very picky...

TBC

I'll be checking coils and plugs but I doubt that's it. It went from running perfect to barely running in one short trip. Couldn't even move it today. Misfires on 5,7 and 8 on code reader now. I thought about cats but wouldn't they go gradually? It idled perfect now it won't run unless you can coax it up to 2500rpm and that's only in park. Can't get it to drive it's running so bad. Battery also went dead and gauges all flicker at zero for about 5 sec. and then go to normal when jump starting. Not sure what killed it. Going to dig into it tomorrow with a new battery to start with. Pulling/inspecting plugs and compression test are first. It had the diesel tick when warm for years, can't hear it now but I can't run it long enough to warm up either. It'll be in my warm shop tomorrow so hopefully I can find something.