MAP Voltages

Having issues finding a suitable replacement MAP sensor. Since I have the GM style connector for my 3 bar, I figured I'd look into a GM 2 bar instead. Below is the pressure to voltage conversion for the GM sensor, I'd assume it's the same with our cars, but figured I'd post it here for anyone to tell me it's wrong.

Manifold Pressure
(relative sea level / absolute)
2 Bar
MAP Output
14.31psi / 29.01psi
4.90V
14.00psi / 28.70psi
4.84V
13.00psi / 27.70psi
4.67V
12.00psi / 26.70psi
4.50V
11.00psi / 25.70psi
4.33V
10.00psi / 24.70psi
4.16V
9.00psi / 23.70psi
3.99V
8.00psi / 22.70psi
3.82V
6.00psi / 20.70psi
3.47V
4.00psi / 18.70psi
3.13V
2.00psi / 16.70psi
2.79V
0.00psi / 14.70psi
2.45V
5.00inHg / 12.24psi
2.03V
10.00inHg / 9.78psi
1.61V
15.00inHg / 7.33psi
1.19V
20.00inHg / 4.87psi
0.77V
25.00inHg / 2.41psi
0.35V
29.10inHg / 0.40psi
0.02V

If you need a new MAP sensor, the 3 & 4 bar Omnipower products came recommended by others.
I think i had purchased my 4 bar from Amazon.

I have a good working 3 bar MAP, what I lack is a good working 3 bar calibration. Waiting for Rob to start selling flashable computers again. Looking for a 2 bar to hold me over.

2bar map or 2bar cal? I may have a spare 2bar map sensor

2 bar map sensor. TIII shows the same map as TI in the efisch, but none of the replacements I purchased worked.

Quote:

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Originally Posted by EaZyE426

but none of the replacements I purchased worked.

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Maybe the issue isn't the MAP sensor?

The 3 bar does not generate a code 14 like the others I've tried. I followed the diagnostic flowchart. If the map voltage is high, replace map sensor. If the map voltage is low, replace ECU. But since the 3 bar worka fine, I'm confident it's not a wiring or ECU issue.

- - - Updated - - -

I can't check the map voltage directly since when I put the volt meter on, the ECU immediately sees 5volts, thinks it at 15 psi, and stalls the car.

Quote:

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Originally Posted by EaZyE426

The 3 bar does not generate a code 14 like the others I've tried. I followed the diagnostic flowchart. If the map voltage is high, replace map sensor. If the map voltage is low, replace ECU. But since the 3 bar worka fine, I'm confident it's not a wiring or ECU issue.

- - - Updated - - -

I can't check the map voltage directly since when I put the volt meter on, the ECU immediately sees 5volts, thinks it at 15 psi, and stalls the car.

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I assume you are "backprobing" the connector while it is attached to the MAP sensor. If so, I suspect there is something wrong with your meter or it is an old analog type. Modern DVM(Digital Volt Meter) have input impedance of 10 M so it will not significantly "disturb" your voltage reading when attached.

I was backprobing, but I was using a modern DVOM. It's a few years old and has seen better days. It rattles of you shake it, maybe something broke loose? Lol