missing, poping, backfiring

[99expo54]

Been going on two weeks now. Start the truck up, idles great. Put it in gear and it sputters pops and backfires for about 20 seconds, then runs fine. Big loss in power all the time though. No codes coming up. All new coils and plugs 2 months ago. New lash adjusters last weekend. What the heck can be causing this?

 

[99expo54]

Pulled drivers side plugs yesterday. Cyl 5-8 were fouled and burnt. Pistons all had rusty crap sitting all over them. Cyl 7 had gauges on top of the piston. Cleaned the plugs and pit them back in. No change. Fuel pressure is in range range but not consistent

 

[stamp11127]

Would have been better to post pics of the plugs electrodes prior to cleaning.

Did you look at the pistons with a borescope?

 

[99expo54]

Would have been better to post pics of the plugs electrodes prior to cleaning.

Did you look at the pistons with a borescope?

Yes i did.

 

[Copper93]

Are the gaps correct and are they the correct plugs and heat ranges? I use to work for an auto parts store and it wasn't uncommon to find plugs in wrong boxes or in the wrong place on the shelf. Had to deal with some upset people. They've been sweating over an engine, busted their knuckles and now the have a plug or two that were wrong.

 

[99expo54]

Are the gaps correct and are they the correct plugs and heat ranges? I use to work for an auto parts store and it wasn't uncommon to find plugs in wrong boxes or in the wrong place on the shelf. Had to deal with some upset people. They've been sweating over an engine, busted their knuckles and now the have a plug or two that were wrong.

Yes gaps are correct. Checked cyl 5-8 the other day. Pulled the plugs on 1-4 tonight, and all looked well. Gapped correctly also. All are the same motorcraft plugs.

 

[99expo54]

Buddy of mine came over last night with a snap on scanner. Everything showed its running correctly, all injectors, coils, sensors, etc.Im sooo lost. Tail pipes smell like gas, and bluish smoke.