+ Reply to Thread
Results 1 to 6 of 6

Thread: 03 4.8 Heavy missfire on Bank 2 HELP???

Hybrid View

  1. #1
    Join Date
    Jul 2008
    Location
    Mesa, AZ
    Posts
    5,979
    Quote Originally Posted by classic_speed_and_customs View Post
    I start my truck and it will run great for a minute or so. Then the whole right bank starts to misfire. Manifold will barely evaporate water. Will ocassionally pick back up around 4000 rpms but die off again instantly. Coils are good and getting power. Changed ECM, MAF, wires, plugs, and checked intake for cracks. Kind of out of ideas. This started when I hit a puddle with the right front tire. Instantly started to miss. Thought I found why when I found my Bank 2 Sensor 1 o2 unplugged but this seemed to have no effect. Any ideas?
    If the O2 was unplugged when you hit the puddle it could have caused the sensor to read incorrectly thus causing the issues explained by Allen. I think replace the O2's and then check it out.
    T-RAV
    99 GMC | 5.3 | Skinny White Guy Tuned

  2. #2
    Join Date
    Mar 2003
    Location
    San Antonio, TX
    Posts
    11,038
    Quote Originally Posted by bangbangskeetskeet View Post
    If the O2 was unplugged when you hit the puddle it could have caused the sensor to read incorrectly thus causing the issues explained by Allen. I think replace the O2's and then check it out.
    Don't quote me, lol, but there was a turbo truck we did, it had the same issue, so i unplugged the o2's, I think it put it in open loop all the time, and problem solved, obviously a temp solution, but it fixed it.

    might wanna try it, i don't recommend racing with it in open loop though, cause it's not tuned for it, but it'll lead you in the right direction.

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts