Low Compression / 2 cylyndrs not firing

I was driving my truck and felt a sudden surge in the decrease of power.
Compression on #1&4 is about 170 but compression on # 2 and 3 is about
125. It seems to have spark but the fuel is not firing, plugs are wet and
therefore only firing on only 2 cylynders. I replaced the wires but no
change. What would cause this and does anyone have any ideas on the
troubleshooting of the problem. Spark may be a bit weak at 2 and 3
cylynders is there a test.

Sounds like a head gasket failure between the #2 and #3 cylinder. Any water
in the oil (check the dip stick); any oil in the radiator fluid?

Paul.

"Calgunz" <jeff.quarles@cox.com> wrote in message
news:01e82c4dcd161c4a6b647e6a576f9975@localhost.talkabouttrucks.com...[color=blue]
>I was driving my truck and felt a sudden surge in the decrease of power.
> Compression on #1&4 is about 170 but compression on # 2 and 3 is about
> 125. It seems to have spark but the fuel is not firing, plugs are wet and
> therefore only firing on only 2 cylynders. I replaced the wires but no
> change. What would cause this and does anyone have any ideas on the
> troubleshooting of the problem. Spark may be a bit weak at 2 and 3
> cylynders is there a test.
>[/color]