Alright so I recently installed a prosport premium boost gauge(electrical with 2step motor) and I’m having issues with it reading correctly.
for some reason when the car is off it sits in vaccum about 2-4 psi and when driving its off by 2-4 as well. I have it currently connected to vaccuum source from underneath the throttle body(the big line).I had it going through my fpr vaccum as well with the same result.
I have a total of 3 vaccum lines, the big vaccum underneath the throttle body, the fpr line, and a another line under the throttle body which only gets vaccum when throttle is engaged(Ie when revving it). the one that has no vaccum at idle is plugged and is not used. while the other 2 are.
My question is the way I have my vaccum lines correct? I have tested the car with a mechanical gauge and it read just fine(22 at idle and boost readings were all correct) so I’m almost 100% sure I do not have any boost leaks or vaccum leaks(well based on what the mechanical gauge read).
btw this a 91 240 with a ka-t.