QuestionThe truck was running rough and the engine light came on so I had it checked. I
was told that there was a misfire in 1 and 2 and that a vacuum leak was a likely
culprit. I fixed a vacuum leak and reset and is still running rough and weak.
Had it checked with the light off and it read that number 5 was misfiring. On
the way home the light came on so I had it checked again and it's showing that
3, 7, and 8 are misfiring. I don't know what to believe. Could you please share
any ideas you might have? Thanks and have a great day.
AnswerHello.
These are common failures. The biggest culprit being the wells that the plugs sit in. they collect water and cause misfires. There are updated boots available which I highly recommend.
If the plugs are damaged, or badly worn, they must be replaced. If left too long, they will ruin the coils.
Other possibilities include water in the fuel, comptor or wiring problems, vacuumn leaks, and low fuel pressure.
