Vacuum Guage and Digital Fuel Gauge

[MetroMPG]

glide question, krousdb...

i'm sure you've calc'd this already, but i'm curious to know: how much of your normal daily commute happens with the engine shut off?

[krousdb]

Originally Posted by MetroMPG

glide question, krousdb...

i'm sure you've calc'd this already, but i'm curious to know: how much of your normal daily commute happens with the engine shut off?

Actually after the discussion on the other thread about coasting with engine off, I began to think about what benefit I was getting and I made a few changes to my routine. First, I decided that I would only shut down if I could bump start by using momentum. So now the only time I use the starter leaving from home and leaving from work. I also identified several steeper slopes that I could just use engine braking (injectors off above 1100) and not lose any distance. The result is about 1/2 as many Ignition on/offs per day. What I am down to is 6 engine shut downs each way averaging 1 mile each. So of my 50 mile daily commute, I estimate 12 miles coasting with the engine off. Another 13 miles is light throttle, high vacuum (15-20 in hg)cruising. Another 12 miles is mild hill climbing, intermediate vacuum 11-15 in hg. The remaining 13 miles is serious hill climbing, low vacuum (7-10 in hg).

Many think that hills are bad. But as long as you keep your speeds moderate, below 50 when aero drag really kicks in, hills are quite good. This is because your engine is more efficient when working hard climbing hills as opposed to cruising. Even though I burn more fuel going up the hill, I also gain potential energy which is released free of charge while coasting downhill with engine off or engine braking with injectors off. In the end I believe the hilly route will be better than the flat route unless you have a D15Z1 which will give you lean burn under cruising conditions.

With the help of SVOboy I will be trying to simulate lean burn in my D15B7. For the 1/2 of my commute that the engine is on and vaccuum between 10 and 20 in hg, lean burn could reduce consumption by 10-20%, or 5-10% for the entire 50 mile trip.

[krousdb]

End of Day #1, 58 actual miles, 11.7 Ohms, 1.08 gallons, 53.7 MPG
End of Day #2, 110 actual miles, 15.9 Ohms, 2.125 gallons, 51.6 MPG
End of day #3, 163 actual miles, 20.6 Ohms, 3.125 gallons, 52.3 MPG
End of day #4, 182 actual miles, 23.2 Ohms, 3.675 gallons, 49.4 MPG
End of day #5, 235 actual miles, 27.6 Ohms, 4.563 gallons, 51.6 MPG
End of day #6, 286 actual miles, 33.8 Ohms, 5.583 gallons, 51.2 MPG
End of day #7, 339 actual miles, 39.1 Ohms, 6.313 gallons, 53.7 MPG
End of day #8, 390 actual miles, 50.9 Ohms, 7.667 gallons, 50.9 MPG

Obviously a non-linearity in the 6 to 7 gallon region.

[krousdb]

End of Day #1, 58 actual miles, 11.7 Ohms, 1.08 gallons, 53.7 MPG
End of Day #2, 110 actual miles, 15.9 Ohms, 2.125 gallons, 51.6 MPG
End of day #3, 163 actual miles, 20.6 Ohms, 3.125 gallons, 52.3 MPG
End of day #4, 182 actual miles, 23.2 Ohms, 3.675 gallons, 49.4 MPG
End of day #5, 235 actual miles, 27.6 Ohms, 4.563 gallons, 51.6 MPG
End of day #6, 286 actual miles, 33.8 Ohms, 5.583 gallons, 51.2 MPG
End of day #7, 339 actual miles, 39.1 Ohms, 6.313 gallons, 53.7 MPG
End of day #8, 390 actual miles, 50.9 Ohms, 7.667 gallons, 50.9 MPG
End of day #9, 445 actual miles, 63.1 Ohms, 8.563 gallons, 52.0 MPG
End of day #10, 477 actual miles, 75.2 Ohms, 9.190 gallons, 51.9 MPG

[SVOboy]

Looks like you're doing pretty well this tank.

I just bought my new thermostat. I'll send you my old one and you can compare and hopefully learn they're the same and can therefore get mine for 7 bucks,

I hope the lady put the 195 in the box and not the 170,

[krousdb]

Originally Posted by SVOboy

Looks like you're doing pretty well this tank.

I just bought my new thermostat. I'll send you my old one and you can compare and hopefully learn they're the same and can therefore get mine for 7 bucks,

I hope the lady put the 195 in the box and not the 170,

I just stopped by Autozone and ordered the 192F thermostat for $17. It should be in on Tuesday. Stopped by the Honda dealership and ordered the engine block heater for $42. Should be in by Friday.

[krousdb]

End of Day #1, 58 actual miles, 11.7 Ohms, 1.08 gallons, 53.7 MPG
End of Day #2, 110 actual miles, 15.9 Ohms, 2.125 gallons, 51.6 MPG
End of day #3, 163 actual miles, 20.6 Ohms, 3.125 gallons, 52.3 MPG
End of day #4, 182 actual miles, 23.2 Ohms, 3.675 gallons, 49.4 MPG
End of day #5, 235 actual miles, 27.6 Ohms, 4.563 gallons, 51.6 MPG
End of day #6, 286 actual miles, 33.8 Ohms, 5.583 gallons, 51.2 MPG
End of day #7, 339 actual miles, 39.1 Ohms, 6.313 gallons, 53.7 MPG
End of day #8, 390 actual miles, 50.9 Ohms, 7.667 gallons, 50.9 MPG
End of day #9, 445 actual miles, 63.1 Ohms, 8.563 gallons, 52.0 MPG
End of day #10, 477 actual miles, 75.2 Ohms, 9.190 gallons, 51.9 MPG
End of day #11, 501.5 actual miles, 90.8 Ohms, 9.680 gallons, 51.8 MPG

Filled 9.68 gallons. Starting new tank.

[SVOboy]

Oh schnizzle that was some on target jive.

[krousdb]

Originally Posted by SVOboy

Oh schnizzle that was some on target jive.

Yes, at the end of the tank it is very accurate due to the faster rate of change of the reading. But you can see in the middle of the tank the numbers bounced around a bit. Still, much better than trying to eyeball a analog gauge.

After I install the SuperMID I won't need the digital fuel gauge. I will reconnect the analog gauge and you can have my DMM if you want it. Another knick knack for free. A small token for all of your help. ;-)

[SVOboy]

That'd be fly! I need to give my teacher back his DMM, and his huge battery, and his power drill...

He'd be mad if he knew I had it all.