bordin34

Also interesting how the 928 speedometers stop at 85 while the 944 goes up to 160. They also got rid of the MPG gauge in the 944 after the 86 model year.

WallyP

From the service info by year for 1982:

The electronic circuit of the fuel consumption indicator requires two input signals.
1. The vehicle speed in MPH (km/h)
2. The fuel injection quantity.

The injection quantity is supplied by the injection signal “Ti” from the AFC - control unit.
The signal comes in the form of sine wave impulses with a variable impulse length and indicates the fuel quantity being injected at any given time.

The vehicle speed signal comes from the sending unit for the electric speedometer.


These little booklets include some fascinating reading.

BRB-83-911SC

Only for certain years as mandated by the US Feds. Most go to 170. I also have the Fuel Economy guage in my 84 Euro in terms of L/100km.

Randy V

Those GPM gauges were a kinda jinky requirement by the CAFE standards in place back then as a way to offset the gas mileage requirements.

In theory, the driver would monitor that gauge to optimize fuel economy.

In real life they really didn't add any value.

STRIKEMASTER

I have an MPG gauge in my '83 euroS and it's always pegged to the max. I wonder if it is even hooked up??