Scan gauge schooling
#181
05-25-2008, 11:40 AM
I think something changed with my car... I got to 315 miles before the fuel light came on. Filled up at 326, and got 9.9 gallons in.
SO.. I think my fuel light is coming on 'later' in the tank than it was before.
SO.. I think my fuel light is coming on 'later' in the tank than it was before.
#182
05-25-2008, 12:01 PM
Not sure if any of you watch Mythbusters (cool show) but they did an episode on A/C vs. Windows down:
Tests were performed under varying conditions (55 mph versus 45 mph). The 55 mph test used a computer to estimate fuel efficiency based on air intake, not actual fuel consumption, and showed A/C was more efficient. The 45 mph test consisted of running the tank until it was empty, and showed open windows were more efficient. *Because the original tests were inconclusive, this "urban puzzle" was revisited in episode 38: It is more fuel efficient to use air conditioning when the car is traveling approximately 50mph or more. Otherwise, windows are more fuel efficient.
Tests were performed under varying conditions (55 mph versus 45 mph). The 55 mph test used a computer to estimate fuel efficiency based on air intake, not actual fuel consumption, and showed A/C was more efficient. The 45 mph test consisted of running the tank until it was empty, and showed open windows were more efficient. *Because the original tests were inconclusive, this "urban puzzle" was revisited in episode 38: It is more fuel efficient to use air conditioning when the car is traveling approximately 50mph or more. Otherwise, windows are more fuel efficient.
#183
05-25-2008, 12:45 PM
One thing to remember about pumping fuel.
If the pump says 5 gallons, you don't have 5 gallons by volume due to pump correction for temperature.
Take your 5 gallon gas tank and put 5 gallons in it by reading the pump.
Now look at the gas can.
You will be missing at least a quart (or litre for us Canadians) or two!
I was told that the volume in the gas can will expand to give me the correct amount but my primitive tesing shows otherwise.
If the pump says 5 gallons, you don't have 5 gallons by volume due to pump correction for temperature.
Take your 5 gallon gas tank and put 5 gallons in it by reading the pump.
Now look at the gas can.
You will be missing at least a quart (or litre for us Canadians) or two!
I was told that the volume in the gas can will expand to give me the correct amount but my primitive tesing shows otherwise.
#184
05-25-2008, 02:46 PM
Not sure if any of you watch Mythbusters (cool show) but they did an episode on A/C vs. Windows down:
Tests were performed under varying conditions (55 mph versus 45 mph). The 55 mph test used a computer to estimate fuel efficiency based on air intake, not actual fuel consumption, and showed A/C was more efficient. The 45 mph test consisted of running the tank until it was empty, and showed open windows were more efficient. *Because the original tests were inconclusive, this "urban puzzle" was revisited in episode 38: It is more fuel efficient to use air conditioning when the car is traveling approximately 50mph or more. Otherwise, windows are more fuel efficient.
Tests were performed under varying conditions (55 mph versus 45 mph). The 55 mph test used a computer to estimate fuel efficiency based on air intake, not actual fuel consumption, and showed A/C was more efficient. The 45 mph test consisted of running the tank until it was empty, and showed open windows were more efficient. *Because the original tests were inconclusive, this "urban puzzle" was revisited in episode 38: It is more fuel efficient to use air conditioning when the car is traveling approximately 50mph or more. Otherwise, windows are more fuel efficient.
From test results
windows don't make much matter at 55 or less
A/C sucks gas like crazy. At least 3mpg decrease min
#186
05-25-2008, 05:01 PM
It's not so much what the needle points to that is of concern. It seems to be at the same deflection when the light comes on.
It's the capacity to full that seems to have increased when the light is activated. Now I'd estimate it's closer to 9.5ish gallons.
It's the capacity to full that seems to have increased when the light is activated. Now I'd estimate it's closer to 9.5ish gallons.
#187
05-25-2008, 05:23 PM
BTW 9.5 is about what mine is and always has been
#188
05-25-2008, 05:52 PM
OK I have my gauge and I'm using it to find out what works best on my Fit.
1st
Short shifting @ 2000 (as I started doing) with any acceleration is NFG. As I kind of suspected it loads the eng and the mpg is 12 to 15. Raise it to 3000 and it's well over 20mpg as you go up in speed. I will try more RPM's and find the best shift point.
2nd
It's true when you see a light and want to slide in with least fuel (with eng on) coasting in neutral is 0.25gph no A/C and .4 w A/C. Lift off the gas in 5th gear and it's 0 gph till you stop. real time MPG calc goes to 9999
3rd
It's 80F here, but when the eng is cold and not up to temperature the combustion controls does go into closed loop very fast. In fact, in less than 15 sec's from over start on an night stop. This is long before the cold eng light goes out. Was wondering about that. Bottom line, don't wast a sec idling to warm engine, if you want to save gas. No idea how that is in very cold areas of the world???
info bud
at 45mph in 5th steady cruse the Fit gets 50+ mpg
HAs anyone else got some stuff to offer.
I'd like to try a taller tire some day. Anyone try that and document the mpg change?
1st
Short shifting @ 2000 (as I started doing) with any acceleration is NFG. As I kind of suspected it loads the eng and the mpg is 12 to 15. Raise it to 3000 and it's well over 20mpg as you go up in speed. I will try more RPM's and find the best shift point.
2nd
It's true when you see a light and want to slide in with least fuel (with eng on) coasting in neutral is 0.25gph no A/C and .4 w A/C. Lift off the gas in 5th gear and it's 0 gph till you stop. real time MPG calc goes to 9999
3rd
It's 80F here, but when the eng is cold and not up to temperature the combustion controls does go into closed loop very fast. In fact, in less than 15 sec's from over start on an night stop. This is long before the cold eng light goes out. Was wondering about that. Bottom line, don't wast a sec idling to warm engine, if you want to save gas. No idea how that is in very cold areas of the world???
info bud
at 45mph in 5th steady cruse the Fit gets 50+ mpg
HAs anyone else got some stuff to offer.
I'd like to try a taller tire some day. Anyone try that and document the mpg change?
#192
05-25-2008, 09:04 PM
#194
05-25-2008, 11:39 PM
Coasting in neutral will go to way high MPG numbers... but coasting in gear and getting DFCO will get ∞MPG!
#195
05-25-2008, 11:42 PM
It does. CONFIRMED.
(as long as you cut throttle at >1500RPM or so, it will cut fuel down to about 1100RPM)
(as long as you cut throttle at >1500RPM or so, it will cut fuel down to about 1100RPM)
#196
05-30-2008, 10:48 AM
@PCS Thanks for all the great info!
This brings up another nagging question...when I turn the car on, there is a 2-3 second delay before SG lights up. Has anyone tried to figure out how much gas burned that it missed? Or does it assume a certain amount was used for startup based on the engine size? It seems like even if I get going on a decline and the realtime mpgs are very high, it takes a while for the trip mpg to catch up. I wondered if that might have something to do with it?
This brings up another nagging question...when I turn the car on, there is a 2-3 second delay before SG lights up. Has anyone tried to figure out how much gas burned that it missed? Or does it assume a certain amount was used for startup based on the engine size? It seems like even if I get going on a decline and the realtime mpgs are very high, it takes a while for the trip mpg to catch up. I wondered if that might have something to do with it?
#197
05-30-2008, 11:35 AM
To follow up with some additional SG facts..... I told you over the last few weeks that the SG does not log miles travled when the eng is off and your rolling. It does not matter if the key is in position II or I. How this plays with the accuracy of our SG got the best of me and today I did some testing.
As I got rolling on my freeway part of my commute today, I reset the trip odometer on my Fit and reset the SG current trip meter and than watched both. At the end of 10 miles the Fit read 10.0 and the SG 9.9. Pretty decent
So why is my SG miles and mpg always less than the pump Fit trip calc? I know why now. I do some eng off coasting as part of my hypermilling. That's limited to two ways. I kill the eng and roll into a light that changed red when the wait is expected to be more than 15sec. I also on occasion roll off my main street up my neighbor-hood street, up my driveway and into my garage. I do that just because it's an odd chalange, but of course that has some eco rewards. At most, I do that 50% of the available times because of cars in the path. I only do it when no cars or humans are around. It is about 1/4 mile coast max. but involves 2 turns at faster speeds than
normal". I never FAS, as my feeling after doing it a few times is, it was just too much work for the reward. I drive on flat land so have no hills like most of you to coast down.
OK back to the miles issue. As I exited the freeway today, like normal I killed the eng and coasted to this 1st LONG wait light with eng off. From that point, to my office may do it 2 more times. What I recorded when I arived at work was: 18.2miles Fit odometer and 17.2 SG from that point I reset both. So close to a mile of eng off coasting showed up. In addition, looking at the tank miles, I'm at 191 on the Fit odometer and 182 on the SG. That's 5%.
Bottom line the SG is vary accurate with no trim on minel. But, if you coast it throws off the miles and than the MPG for ALL the trip readings. I'll have to look at the written records I have at home and see if this 5% is about what the delta is. I know I calculated that in my spread sheet. This week my SG says I/m 44mpg for the 182 miles and I'm at 2/3 tank of gas left now. So by the numbers I'm really at around 46mpg.
I'm going to contact SG and ask them if they can do something to make it record the coasting miles with ign on... ie switch in pos II
Hope this helps someone
As I got rolling on my freeway part of my commute today, I reset the trip odometer on my Fit and reset the SG current trip meter and than watched both. At the end of 10 miles the Fit read 10.0 and the SG 9.9. Pretty decent
So why is my SG miles and mpg always less than the pump Fit trip calc? I know why now. I do some eng off coasting as part of my hypermilling. That's limited to two ways. I kill the eng and roll into a light that changed red when the wait is expected to be more than 15sec. I also on occasion roll off my main street up my neighbor-hood street, up my driveway and into my garage. I do that just because it's an odd chalange, but of course that has some eco rewards. At most, I do that 50% of the available times because of cars in the path. I only do it when no cars or humans are around. It is about 1/4 mile coast max. but involves 2 turns at faster speeds than
normal". I never FAS, as my feeling after doing it a few times is, it was just too much work for the reward. I drive on flat land so have no hills like most of you to coast down.
OK back to the miles issue. As I exited the freeway today, like normal I killed the eng and coasted to this 1st LONG wait light with eng off. From that point, to my office may do it 2 more times. What I recorded when I arived at work was: 18.2miles Fit odometer and 17.2 SG from that point I reset both. So close to a mile of eng off coasting showed up. In addition, looking at the tank miles, I'm at 191 on the Fit odometer and 182 on the SG. That's 5%.
Bottom line the SG is vary accurate with no trim on minel. But, if you coast it throws off the miles and than the MPG for ALL the trip readings. I'll have to look at the written records I have at home and see if this 5% is about what the delta is. I know I calculated that in my spread sheet. This week my SG says I/m 44mpg for the 182 miles and I'm at 2/3 tank of gas left now. So by the numbers I'm really at around 46mpg.
I'm going to contact SG and ask them if they can do something to make it record the coasting miles with ign on... ie switch in pos II
Hope this helps someone
#198
05-30-2008, 07:40 PM
damn. i never realized how LONG some redlights can be. i got stuck in a 4 minute light. i shut off the engine and a whole song played on my cd player lol
#199
05-30-2008, 10:22 PM
Paul: do you have your scangauge fuel type set to "hybrid" ? If you have it set to "gas" you'll see just what you are experiencing. You need to tell the SG you're driving a hybrid so it keeps "thinking" even when the engine is off. I always get ~77 miles from my home back to the old neighborhood no matter what I'm doing with the engine.
#200
05-31-2008, 09:46 AM
Rich, Can you list the key strokes to set or check that? I have the blue book and just looked and must of over looked that. I have mine set for 1.5l gas. Guess you are saying your SG does not do that???
Shawn. I use a "4 cup" (max) kitchen accurate measuring cup, 4 times as listed above. It should be very close That's the best I have. BTW The reason I did not use a RED gas jugs, none seem to have marks to show volume. They are also hard to see when looking at the level because of the thick red plastic. For me it's just a temp. deal as soon as I get home I'll transfer the gas into my mower or wifes car.
Shawn. I use a "4 cup" (max) kitchen accurate measuring cup, 4 times as listed above. It should be very close That's the best I have. BTW The reason I did not use a RED gas jugs, none seem to have marks to show volume. They are also hard to see when looking at the level because of the thick red plastic. For me it's just a temp. deal as soon as I get home I'll transfer the gas into my mower or wifes car.
