Hey all,
I recently installed a brand new Omori boost gauge in the cluster of my mr2 and have an issue with it.
 
It will not display boost, only vacuum.  So for example, if I am driving the car it will not go past around 5 inHg under WOT (I know for certain I am running 16 psi when using a mechanical boost gauge).
 
Under no load (revving when car is stationary), it will not go past 5 inHg.
 
I am 99% certain I have wired the boost gauge up correctly: 
 
Red - +12v ignition
White - illumination (+12V to illuminate - took it off one of the dash lights)
Black - ground
Green - +12v from battery
 
The needle will also complete the 270 degree sweep when ignition is turned on, then remain at the 7 o'clock position/20 inHg vacuum.  Illumination works when the parkers/dash lights are turned on.
 
So I need to narrow down whether its the sender or the gauge.
 
1.  When the car and ignition is off, the needle will be at the 6 o'clock position (30 inHg). Is this normal?
 
2. When the ignition is turned of the needle will complete the 270 degree sweep, then remain at the 7 o'clock position/20 inHg"  Is the 7 o'clock/20 inHg position normal? 
 
3. When the car is started, the needle will be showing 20 inHg.
 
4. When under load, the needle moves from 20 inHg to 5 inHg.
 
It never gest past the 0 into boost.
 
 
 
 

1) Yes that's normal.

2) The 270 degree sweep is normal when the gauge first gets ignition power.
After the sweep, with the engine off, the needle should be at 0 (atmospheric pressure). I don't know if your Omori gauge has the same face as mine, but in my case that's 9 o'clock not 7 o'clock.

3) Do you mean 20inHg, not 20psi? If so, that's about right.

4) It could be a faulty sensor, or you could have an air leak which only shows up under boost but not under vacuum.

Also check that the needle isn't rubbing against the gauge face. That happened to mine and I had no idea until I had the cluster out again and saw it from side-on.

robk
1) Yes that's normal.

2) The 270 degree sweep is normal when the gauge first gets ignition power.
After the sweep, with the engine off, the needle should be at 0 (atmospheric pressure). I don't know if your Omori gauge has the same face as mine, but in my case that's 9 o'clock not 7 o'clock.

3) Do you mean 20inHg, not 20psi? If so, that's about right.

4) It could be a faulty sensor, or you could have an air leak which only shows up under boost but not under vacuum.

Also check that the needle isn't rubbing against the gauge face. That happened to mine and I had no idea until I had the cluster out again and saw it from side-on.

Thanks for that Rob, fixed my OP in regards to vacuum abbreviation.
 
2) The 270 degree sweep is normal when the gauge first gets ignition power.
After the sweep, with the engine off, the needle should be at 0 (atmospheric pressure). I don't know if your Omori gauge has the same face as mine, but in my case that's 9 o'clock not 7 o'clock.
 
That's correct, mine is at 7 o'clock position - it doesn't go back to 0 (9 o'clock).  I disconnected the sender and with the ignition on, it stays at the 6 o'clock (30 inHg) after initial sweep.