jiminem2

Hey guys!
Got a 2004, v8 5.4 Triton. 160k Just brought in may, so I don't know tune up history.

This started out as a bad cat code, with occasional misfire like bump at about 45mph. The misfire has progressed to going uphill and any fast acceleration 40-60mph. Especially towing. It's got a system too lean bank 1 code. I believe the bad cat is on this side as well, right cat. I wondering if the misfire caused the bad cat.

Problem is, I only occasionally pickup P0302 cylinder 2 misfire code, and its seems to be only pending when it does show. The engine light starts flashing and I plug my code reader in right then and see it displayed. Next day its gone!

It looks like somone replaced all the coils, because they are white vs black. All but two, the two original coils are on the right side, but cylinder 2 looks to have a new coil!

What should I do here? Replace plugs & coils on bank 1 / right side? I intend on using a shop, I'm scared about the spark plug thread issue.

Thanks yall

Martian

If you don't know the tune-up history, prepare to replace ALL your plugs

techrep

iTrader: (1)

And white COP's ?? you could swap one out on #2 and see if the DTC follows it.. agree with doing all the plugs...a flashing CEL indicates a mis-fire condition.. a mis-fire will dump raw fuel into your Cat's and cause it to become clogged.

gone postal

System too lean w/misfire can also indicate a clogged injector.

techrep

iTrader: (1)

Agree

jiminem2

Thanks sir. How would they check for clogged injector is this a visual inspection? What would this mean if it was bad, new one or clean it?

gone postal

The only way to "check" an injector is to pull it and bench test it. I had a similar situation, and I found a set of injectors on ebay and replaced them. It probably cost me less to replace the injectors than have them tested.

If the lean code and the misfire are on the same bank, I'd start there, especially as the coils appear to be new.

jiminem2

Problem was a bad coil on cylinder 2. not original coils but they're some generics, white in color. Not yet sure if it was related to system lean code.

techrep

iTrader: (1)

Good to hear...