fitzpats

Hey everyone. Hopefully I can get put on the right path. My truck's SES light came on a few days ago, and I had it checked. Said that it was running lean on banks 1 & 2. Had this happen last year in the cold, so I cleaned the MAF and it's been good until it got cold again. I haven't cleaned the MAF as I haven't had time. Naughty me.

Today, the truck started running rough, so I left it at home and took the wife's vehicle as I didn't have time to dig into the problem earlier. Just got back from Advance where I had the codes read again, and this time it added misfires on cylinders 1, 3, and 5. Purchase plugs to replace all 8, but just wanted to make sure that I was on the right path.

Oh year, 2000 F150 Lariat. 215k+ miles on it. 5.4 Triton, 4wd. Thanks for any help that I can get.

Tackle

It is likely your plugs aren't the problem.

Won't hurt to change them though.

SouthernSteel

Disconnect the negative battery cable to reset PCM, and replace the plugs. If MIL comes back on after have the codes checked again. You're on the right path. When's the last time plugs were swapped?

fitzpats

It's probably pushing two years since I've changed the plugs. I'm thinking somewhere between 35k - 50k miles since I've swapped them out.

SouthernSteel

If you did OE motorcraft plugs I wouldn't think they'd be bad yet. Unless Fords changed it, it used to be 100k miles. Could be wrong on that though. Without diagnosing its hard to say. Could be an injector, cop, etc. I'd go ahead and swap plugs. Make sure to check if the missing cylinders are fouled. Then like I said see if MIL comes back on.

fitzpats

Tonight, I replaced all 8 spark plugs and cleaned the MAF. When replacing the plugs, I unhooked the negative cable from the battery so it reset the MIL light. After all was done, I took the truck for a four mile test drive and it still felt like it was misfiring though no light came on. Guess I'll have to drive it some more and see if the MIL comes back. Anyone with any thoughts before I get the code?

Frank_Ford

When you change your plugs be on the lookout for other problems. Things like oil and coolant that might be leaking into the plug sockets. Bad connections between the COP's and your plugs. I always like to make sure the plugs sockets are clean when I install new plugs. I clean them with a round plumbers wire brush, WD40 and rags. I also use di-electric grease on the connections. That way I know I have a good connection and the plugs are in tight. If you still have a miss, check the fuel injectors

fitzpats

Truck finally threw another code, so I had it checked out. Got a P0174 code. Thinking it's the O2 sensor since the MAF typically throws P0171 and P0174. Am I wrong in my assumption? Any ideas why only bank two would be running lean?

TheUnforgiven71

Have you checked ypur wire set, mine was running horrifing rough with misfires changed my wireset n she runs like a beauty again.

fitzpats

After a little more research on the internet, I'm wondering if I shouldn't attempt to use some fuel injector cleaner and change the fuel filter. Could those items be causing a lean run on the bank?