DPM trouble shooting

[eazyduzit509]

So, i tried to "test" the DPM on my 99X tonight, fired it up without touching the throttle, just a few primer pumps, let it idle for about 20 seconds until it was smooth, unpluged the 4 wire conector for the DPM and NOTHING happened. No engine changes (bogging, idle drop, etc). So, i let it idle and started un-plugging the air hoses to see if something would happen, and no matter which one i unpluged (i believe theres 7, and 1 breather that goes nowhere?) nothing happened. I unpluged the black hose that when standing in front of the sled is on the left of the DPM unit, and saw what looked like light exhaust coming out???

For kicks, i blew in it and the engine bogged down and stalled. Tried sucking it (vaccum effect) and nothing happened, just taste like crap... Any ideas on what could be wrong? I checked ALL the hoses to make sure they were plugged in, which they were, except for the biggest clear hose that is about 6" long and looks like a drain hose?. The lower black hose i unplugged SEEMS to be plugged in, the units under the engine so its hard to see, its covered in grime and grease... I dont know what it could be, i assumed atleast one of the hoses would have some sort of vaccum or pressure behind it and they all seemed pretty neutral. Im stumped, sled runs PRISTINE in the low elv's, and never had a problem with cold starting and idle, always seems to start on 2nd pull after 3 primer pumps. Thanks guys, may be goin sledding next weekend and want a great running sled... We all do.

 

[rdr99]

I think that one of the hoses goes to an air pump under the engine. Never really messed with the DPM so I can't be of much help.

 

[winter brew]

I'm not sure what your symptome are....but on that sled there are 2 things to check that were a problem. Make sure you are running ONLY resistor plugs and also make sure your spark plug caps fit snug AND use a little dielectric silicone gel in the caps. There were issues in '98-'99 with the arcing inside the cap that interfered with the DPM and caused all sorts of wierd symptoms. I had a '98 that would just start running rich and would die....not start for 5 minutes then was fine for awhile and do it again. New plug caps and never had another problem. This was common and there was a bulletin for dealers on this as well.

 

[eazyduzit509]

I put new plug caps on it last year, because it was running right and my dealer said the resistors in the plug would go bad. I was also told the DPM unit that sits on the airbox can leak on the clutch side, he said to silicone it to make sure its sealed. And something about hooking up a 12V battery to the solinoids inside the DPM rail and making sure they "click" to see if there working. The only real reason i think its not working is in higher elevations its lacks power and seems to bog down, but i guess that could just be jetting. Runs great bellow 5000ft. What kind of jets should i run for around 5-8000ft? And other way to TEST the DPM unit?

 

[powderdogx]

sounds like your dpm is ok, how bad is it bogging above 5k? I run the same sled, as with any compensated machine you will lose a slight amount of power with elevation but not much. what is your primary set at? Your springs change rate with elevation which is why the tra's have adjustment for elevation and if they are set too low it will cause bogging. I also found out last season that there are two belts that can be used on that machine, i got the one that i had not been using and it sucked, i had less power and would run a bit boggy up top. I went back to the belt i was using before and it snorted right up like it had before. That could be something to look at also.

 

[eazyduzit509]

sounds like your dpm is ok, how bad is it bogging above 5k? I run the same sled, as with any compensated machine you will lose a slight amount of power with elevation but not much. what is your primary set at? Your springs change rate with elevation which is why the tra's have adjustment for elevation and if they are set too low it will cause bogging. I also found out last season that there are two belts that can be used on that machine, i got the one that i had not been using and it sucked, i had less power and would run a bit boggy up top. I went back to the belt i was using before and it snorted right up like it had before. That could be something to look at also.

well, it pretty much feels like im missing my last 1/4" of throttle, the last (bwaaaa!), kina feels like a small child is clinging to my tunnel... haha. Its to the point that i ask my group if they want to go down lower (dang...) so it dosnt bog out. Its ALOT like having the air filter clogged with snow, which i have experianced as you all have im sure. I touched my clickers for the FIRST time this year, havnt ridin it yet, ran on clicker 3 since i bought the sled, i was also told that could help aswell (on 4 now to see if it helps on my next ride). As for the belt, im on my 2nd one, got it AND my spare from Skidoo, $100 belt. ahhh! Just told him what sled i had and he gave me there best belt (so i ASSUME its correct). Between not knowing what jets im running and anything about clutching i could probly start with the two and adjust as needed...

 

[sledjunky3]

My buddy is having the same problem with his. As soon as it gets into some powder it bogs down. did you find what the problem was?

 

[eazyduzit509]

My buddy is having the same problem with his. As soon as it gets into some powder it bogs down. did you find what the problem was?

No, sled seems to run excellent high and low, the ONLY thing i changed were my clickers up high... thats it.