Actual fuel use

[mathijskok]

It has been discussed here before... one of the things we miss in the 300 is a way to see the actual fuel use, not ther average. Now yesterday I was driven the most boring autobahn and was playing with the systems and I got an idea.

Is the pedal position indicator you can call up linear to the amount of fuel being dumped into the engine? On cruise control I could clearly see the values differ when going uphill (I seen it climb to 95% on a steep hill and cruise control on 105 mph!!!) and downhill. But I am not sure if pedal position is linear to amount of fuel.

[Aleks202]

Ha sounds pretty interesting, but expected.
What did you want us to do? post our fuel usage or comment? Thanks

[LWOOD]

I think I understand what you are saying, but fuel use is relative to load as well as RPM, so your pedal poistion percentage indicator doesn't work as a " total use indicator" in the strictest sense. What I mean is that going down a hill with cruise set at 80 and the pedal position showing 3 % and and driving slowly down a "flat" street with the indicator at 3% don't yeild the same net fuel usage. The load in the two scenarios is different. So, while a higher percentage on the peddle postion indicator indicates in general "more fuel used", you couldn't tell from that number exactly how much more. Also, don't forget about MDS which will not change the pedal position percent when it kicks in, though it is clearly netting a gain in economy. Hope this helps.

[mathijskok]

Originally Posted by LWOOD

I think I understand what you are saying, but fuel use is relative to load as well as RPM, so your pedal poistion percentage indicator doesn't work as a " total use indicator" in the strictest sense. What I mean is that going down a hill with cruise set at 80 and the pedal position showing 3 % and and driving slowly down a "flat" street with the indicator at 3% don't yeild the same net fuel usage. The load in the two scenarios is different. So, while a higher percentage on the peddle postion indicator indicates in general "more fuel used", you couldn't tell from that number exactly how much more. Also, don't forget about MDS which will not change the pedal position percent when it kicks in, though it is clearly netting a gain in economy. Hope this helps.

Actually this was not what I seen (although very hard to be sure). The pedal % seemed to act exactly as the computer readout I see in my other cars. Now I am not totaly sure how to interpret 'load' but does anybody know what the pedal % actually is? Is fuel flow, as I believe it is?

[hystiker]

I agree with Lwood. If your car is sitting in your driveway idling, eventhough throttle will read 0%, the engine is clearly using fuel. When you have your vehicle on a perfectly flat road, the throttle reading will be fairly accurate, but anytime you go over a little bump, the car will close the throttle a little. If you coast down a long hill, the throttle will read 0%, but the engine is still using fuel, otherwise it would die out.

[HemiChemi]

deleted .

[mathijskok]

Originally Posted by hystiker

I agree with Lwood. If your car is sitting in your driveway idling, eventhough throttle will read 0%, the engine is clearly using fuel. When you have your vehicle on a perfectly flat road, the throttle reading will be fairly accurate, but anytime you go over a little bump, the car will close the throttle a little. If you coast down a long hill, the throttle will read 0%, but the engine is still using fuel, otherwise it would die out.

No, it's connected to the wheels and so keeps turning over. At least on other cars I had there was actual zero fuel use when you were in motion and took your foot from the throttle.

But we still don't exactly know what value is actually given, as far as I can see it is not the actual movement of the pedal.

[LeeSoFL]

I miss the real time mpg readout on my '98 Intrepid ES. It would calculate the average mpg and the "on the fly" mpg. On that car it would read about 30 mpg (momentary) when you were on a flat road at about 65mph. Needless to say, it read 99.9 when coasting down hill. Now there's some high mpgs!

[LWOOD]

Originally Posted by LeeSoFL

I miss the real time mpg readout on my '98 Intrepid ES. It would calculate the average mpg and the "on the fly" mpg. On that car it would read about 30 mpg (momentary) when you were on a flat road at about 65mph. Needless to say, it read 99.9 when coasting down hill. Now there's some high mpgs!

And I think that's what the overriding question is here...Can you use the pedal position percentage indicator in the easter egg to figure on the fly mpg, and I say no...Too many variables as i stated above. There is no way to get there from here, so to speak.