Looking for help diagnosing Bog

[Kestrel2126]

So I have picked up an intermittent WOT bog this season, that I have never had. The sled is a 2011 Pro RMK 800 with BD turbo, and has been turboed from '11. I upgraded to Intercooled, TPSmart EBC, and Tial in 2012, and have run the same numbers since then, with excellent results. Since nothing has changed, I don't feel like this should be a fuel number issue. The bog occurs only some of the time, and seems to come and go. When it happens, it is during one of 2 instances. 1) WOT, let off, and then back to WOT. The sled runs clean to WOT, but after let off momentarily and then back to WOT, it bogs hard, and will not clean up. 2) Same circumstances as before, varying throttle and then up to WOT. Sleds hits full boost and target RPM for a second or two, and then bogs hard and falls flat.

This only happens under load (deep snow, uphill, etc.), never on trail or hard pack. I have also noticed that my PTO side plug looks almost fouled, whereas Mag side looks clean and good. Only other thing, is the stock EGT sensor, is throwing a "Voltage Too High" code. I've had this before (different ProRMK), and it didn't affect anything performance wise. Not sure if this could mess with something on a turbo sled? I've got a new sensor on order.
My thought are, Bad Coil or plug wire?, Exhaust Valve?, Voltage Regulator/Capacitor? Bad Aux Injector blowing open at WOT?

Anyone have a similar issue, or have any suggestions? Only code thrown is the EGT probe. Thanks for any help or ideas in pinpointing the issue.

 

[Hollywood99]

had similar issue wth same setup as u it was cracked diaphragm in exhaust valve, real easy fix if that is wat it is and have u changed fuel filter recently

 

[Kestrel2126]

I did change the fuel filter this season. As far as the exhaust valve, I was thinking about that too, but haven't had any time this week yet to wrench. Definitely going to check that out though.

 

[509freerider]

Having the same issue myself, tried contacting Boondocker this afternoon trying to get an idea, but no answer. Mines an 11 also. Mine seems to get better with a higher boost setting, progressively turned it up to 12 and it cleaned it up a bit, but didn't want to go higher running 100ll. Checked all my boots fittings and connections today, but nothing obvious stood out. Would power valves really cause that issue, when ever I've had one out in a NA sled it always was a flat power and never would open up to its full potential? I'm new to the turbo world so I'm learning as I go, just picked up this sled this year, and know a bit about it, runs flawless otherwise.

 

[509freerider]

So I ended up talking with Boondocker and first thing said after telling him the issue was fuel filter, second thing to look at is the fuel pump if changing the filter doesn't work. Also plug gap can come in to play if not gapped correctly and I know I'm off there, think that is some of my low end issue. I'm going to swap my filter tomorrow and keep my fingers crossed!

 

[kanedog]

What is the boondocker recommendation for plug gap?

 

[509freerider]

What is the boondocker recommendation for plug gap?

.018-.020, Out of the box plugs should be about .030 I believe

 

[509freerider]

Installed a new fuel filter and that solved all my issues, ran excellent all weekend!