Standard Map Sensor - R33

[benl1981]

I have tested 2 different gauges on my car - one reads 10psi the other 12psi.

Put boost to stock - one said 7.5psi the other 9.5psi.

I want to use the standard MAP sensor to check boost to give 3rd opinion.

I piggybacked one of the wires and atmospheric pressure reads 2.25v. Is this normal for this sensor. I'm going to run a wire through to cabin and see the peak reading I get on the multimeter.

So 14.7 psi of boost would be 4.5v.

Just wanted to know if the baseline 2.25v seems right (i.e. checking that my sensor is ok)

1psi = 0.153 v

atm + 8psi = 2.25v + 1.22v

= 3.47v

Anybody else done this. I don't trust the granulations on the stock gauge - rather check the actual ouput from the pressure transducer

Edited October 9, 2005 by benl1981

[benl1981]

Just took it for a run - few runs in 2nd saw a max of about 3.2v - about 6.2 psi. Maybe in 3rd might have seen a bit more..had my brother in the car holding the multimeter on the seat bolt ffor the earth etc..

This is at stock boost. So I'm now thinking the gauge that read the low figure was closest to being correct

We'll see once it goes on the dyno and they connect their gauge up.

[benl1981]

Anyone done this?