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hey ppl, just got a used boost gauge from the states, its an apexi el series one, though the gauge while disconnected sits below vaccum at ~7, the gauge works fine, though it sits at 7 (VACCUM PRESSURE)when not in use etc....im pretty sure gauges should sit at 0 when not in use/no pressure, im beginning to think this gauge is going to do more wrong as it will give me incorrect readings?is this true?

i havent hooked it up to my car, but when i recieved it today, it was sitting at the pressure, as most should sit at 0 if calibrated correct?could it need to resync or something when connected back up?

It's an electronic gauge right? So what does it read when switched on, it should read 0 when the sender is open to the atmosphere.

Every electronic gauge i have seen returns to the bottom of the gauge when off, i.e. -1 bar on a boost/vacuum gauge.

(that's not a one-way valve I can see at the back of the gauge in that photo, is it) ??

It's an air filter to stop any crap in the hose going into the guage unit.

Use a T piece, and another piece of small hose. That way you don't cut the original hose.

My mech guage (only for testing) drops to the bottom when off, will come up to -7ish when the motor is idle, will go to the bottom if i'm downhilling it and there is vacuum, and so on... works fine.

It simply doesnt make sense to me that a mechanical guage is not at zero when not connected.

You say yours goes to the bottom when not on? a mechanical guage doesnt have an off or on? its always on? already reading pressure. so when no hose is connected its just reading atmo pressure and should come up as 0.

surely?

lol

Yeah that doesnt look right. I've used two mechanical gauges and they sit at zero when not hooked up or engine switched off.

I guess you can hook up the hose that comes with it and blow into it and see if the needle moves at least

tested gauge yesterday, in terms of running condition, it works!.

wierd experiences.....

i connected the gauge where the fuel pressure reg. is so i can still use my factory gauge for comparison.....and my apexi gauge will get to 0, at the same time as the factory gauge.

When on full boost my car gets to 5 psi on the boost gauge, and the factory gauge shows a bit under +3.5 ( about +2.8 = 6~psi???)

so its seems fairly accurate, though this proves my car is running less than stock boost, and has been since i used the boost solenoid mod trick.....i think the solenoid restricts the boost to 5psi if not connected properly???, and thus the reason why my tap wasnt working???

what do you guys think

tested gauge yesterday, in terms of running condition, it works!.

wierd experiences.....

i connected the gauge where the fuel pressure reg. is so i can still use my factory gauge for comparison.....and my apexi gauge will get to 0, at the same time as the factory gauge.

When on full boost my car gets to 5 psi on the boost gauge, and the factory gauge shows a bit under +3.5 ( about +2.8 = 6~psi???)

so its seems fairly accurate, though this proves my car is running less than stock boost, and has been since i used the boost solenoid mod trick.....i think the solenoid restricts the boost to 5psi if not connected properly???, and thus the reason why my tap wasnt working???

what do you guys think

Easy test - What does it read at idle when warm and without the a/c on? If it is around 20in/hg then it should be correct.

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