Boost Gauge / Vac Q on 06 Apex Mtn. S/C

[Colorado Yamaha]

Buddy just put on new liquid boost guage - last gauge he thought was inop, not showing full boost & needle was bouncing around.

After 2 days ride, returning from 10k to 6500k feet, gauge showed needle at 0, or just slightly to the right. After running heater to melt off snow on sleds, gauge showed -10 on the vac side. Once trailer got cold again, gauge showed 0. Ran the heater today to do some work, gauge showed
-5. ?? Is this a bad gauge - sled was never running, just sitting in the trailer. This is on a MPI Stage I S/C. Thanks, Derek

 

[HAMMER]

I had good luck with the VDO boost gauge this winter. The liquid filled pro series are nice gauges but do not equalize to pressure when you go from inside to outside. Needing to have a bleed screw opened alot of the time. If you leave the screw cracked open they usually leak.

 

[olddodge]

warmer temps mean less atmospatric density, cooler temps have more.
set you gauge at the av temp you ride at, not in your warm shop.

 

[rxrider]

Colorado Yamaha - Did your friend take the vacuum/pressure signal from all 4 intake boots tied together? If not the boost meter needle will bounce around. I have a Autometer (without liquids) and it is stable as soon as I reach take off rpms.

 

[Colorado Yamaha]

RX - no, his boost tube comes straight off the I/C bung, it has one T that ties into the programmer and then straight to the gauge.