howdy, well im trying to figure out my electrical on my trucks pyrometer, when i hit the brakes the pyro will go from normal down to below 2, normal as in 4ish in town driving. so what could be causing this, i know we have all our own wiring styles how we hooked it up, but what do you all figure could be it? that has to do with brake lights.

 

Bad ground ,run the ground to the battery, it fixed mine

 

if it flutters on and off then ya fixed mine too if it flutters without losing power i dunno what to tell you

Jared

 

i think its because the wiring that it is hooked to is not isolated so there is a draw or back flow through it, i think.

 

hmm, well ill try grounding it to the battery, i thinks it's grounded to the dash frame metal, and i went into the back of the pyro and rewired that, but it still flutters, not as bad, but still does.

 

i think you need to isolate the power wire so there is no surge voltage to it. do you still have the factory diagram/instructions for it what do they say to hook to?

 

Power is pretty much to a switched on source. I had the same problem. I shared grounds for all my guages, and when I grounded to a bolt at the engine block all was well. I elieve if you run fuel pressure guages of the mechanical type you must run a seperate ground to avoid flutter, also.