01 summitt 800 carb problems

When DPM fails it goes full rich. DPM is purely an enleanment system, it only leans across the entire fuel curve from your baseline jetting. Sorry if you know this already. It has a max temp and elevation in the MPEM, 10k feet and something like 75 degrees F (sorry, don't recall the precise temp).

You can also test the DPM device itself to verify it can operate with a 9v battery and a paper clip, motor off. Unplug it, use the 9v and a wire/paper clip inserted to the hot wire and you'll hear, and feel, it click as you connect. Hose connections are crucial for it to work when running the sled, and they must be open and free of fuel sitting in them.

I do believe most/all hill climb racers disabled DPM back in the day, and jetted to relative air density during runs. In 04, doo even offered a non-DPM summit 151 for those who were modding, and racing, summits, without DPM. DPM worked better than any of the other non-EFI systems devised for air and altitude adjustments, but still had limitations within the MPEM. But even some mod sleds could use DPM. I built an 04 ported, piped, and head cut Summit that ran well with DPM, after extensive jetting changes. My 2000 and 2001 Summits were stock, and DPM worked perfectly, but they were not raced. Be aware, also, that summit MPEMs and MXZ MPEMs had different fuel curves, if you're swapping MPEMs and running DPM. Just fewer gremlins to chase. Good luck.