2010 d8 down to 1 cylinder

[rmkpolaris]

Sled has ran perfect for me for the last 2 seasons. Last ride, it would have the odd bog & backfire that i assumed was from sucking in the super fine powder we were in (i havent siliconed the headlight adjuster yet). monitored temp constantly and never saw more than 127deg. sled started fine all day and still seems to have good compression on both cylinders. after stopping for lunch it started and ran fine, we took off and i made it about 3/4 mile and it went down to 1 cylinder and the check engine light started flashing. pulled the plugs and pto side was good, mag side was white. still assuming it was moisture, i added isopropyl and left in in the heated shop for 2 nights. still will only run on 1 cylinder. has new plugs & good spark, and mag side plug is wet after starting. im lost with the CFI, where do i start?

i am running a PC5 w/dynotech map (for stock d8) & mbrp can

 

[Ryeser]

Sled has ran perfect for me for the last 2 seasons. Last ride, it would have the odd bog & backfire that i assumed was from sucking in the super fine powder we were in (i havent siliconed the headlight adjuster yet). monitored temp constantly and never saw more than 127deg. sled started fine all day and still seems to have good compression on both cylinders. after stopping for lunch it started and ran fine, we took off and i made it about 3/4 mile and it went down to 1 cylinder and the check engine light started flashing. pulled the plugs and pto side was good, mag side was white. still assuming it was moisture, i added isopropyl and left in in the heated shop for 2 nights. still will only run on 1 cylinder. has new plugs & good spark, and mag side plug is wet after starting. im lost with the CFI, where do i start?

i am running a PC5 w/dynotech map (for stock d8) & mbrp can

Time to get the "fix kit"... same thing happened to me...

 

[dragonweld28]

Your piston and cylinder are done. Time for a new top end. Go with the fix kit.

Pull yur power valves off the one side and im sure you will see some real bad scoring on the front of the piston.