SimpleManLance

iTrader: (9)

this is on the 2005 truck

apparently this misfire is the reason as to why my truck wont lock the TC. so im trying to figure out the problem.

i just (an hour ago) replaced the plugs(drivers side plugs were black), wires, and coils. with all brand new stuff. then i swapped MAFs with my 03 sierra. still had the code. then i sprayed carb cleaner around the intake to see if i had a intake leak. no change in RPMs or tone change.

i scanned the truck and it looks like bank 1 o2 is putting out around 20-30mv where bank 2 was 700-900mv bank 1 injector pulse was a lot higher then bank 2.

could any of these be causing problems or are they some of the effects of the problem(s).

terravast4

iTrader: (25)

maybe a rich condition in bank one took out your converter causing a misfire under load.

dmelvin

iTrader: (8)

Yes, sounds like Bank 1 upstream O2 is just about dead.

SimpleManLance

iTrader: (9)

replaced bank 1 o2 and it shows that it is working properly. still throwing the p0300 code

dewmanshu

iTrader: (4)

as in still flashing? You know the flashing means the misfire is currently happening. The set code (no flashing) is a history.

Have you reset?

262_NBS

a 300 code indicates a multiple cylinder misfire

301 would be a single cylinder missfire @ cylinder #1
302 would be cyl #2

etc