miles off a tank
- Thread starter Matsuda03
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BoostedPR5
Member
I used cruise on mine on my trip to pa and it seemed to do alright. Mines not an auto so it can't really downshift but it stayed pretty even on the speed.
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- Protege5 2003
I have yet to see a car manual which does not recommend against using cruise control in the hills. That said, our Subaru wagon's cruise control works just fine in rolling hills and grades which are not hideously steep. My automatic P5, on the other hand, has a nasty tendency to downshift unexpectedly going up slight grades at highway speeds. That has nothing to do with the cruise control per se, but it will happen when that is engaged too. For those of you have not experienced this dramatic downshift, a fair simulation can be achieved in any manual car by driving along at 65 mph, and then stomping the clutch without releasing the throttle.
I use cruise control frequently when highway/freeway driving. My P5 is a manual transmission, so it uses throttle only to maintain speed whereas the RPMs remain constant.
carter1551
Member
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- 03 Mp5
right but why cant it just keep a speed? why does it push down on the throttle, then let off then push down. I can do it with my own foot just fine and acheive 28mpg easily at a consistent speed where as my mpg is constantly fluctuating with cruise because it cant hold a speed
Yeah that's what mine used to do. Do you have the sport shift? If so, you could always shift to manual mode and leave it in 4th while on cruise...
I have a manual and I find the cruise to work fine, however I hate the reduce speed mechanism. All the other cruise controls I have used the increase speed adds about a MPH to the speed you are set at (with one push, like the P5), and the decrease speed subtracts 1 MPH. On this I have to hold the button down until I glide to the speed I want. This is just annoying.
Also, I have only had my car for a couple of months now, but have not broken the 400 MPT. Yesterday I refilled with 11.95 gallons (the meter was below E and the light had been on for about 20 miles) and had 392 miles since last refill. I have an 03 (maybe 03.5, don't know how to tell) and the manual stated that the tank was 13+ gallon, not 14 though. Did they reduce the tank size? Oh and that was with 90% highway driving, with low-moderate aggressiveness and one 7 mile backup, averaging about 65 MPH excluding the jam.
Also, I have only had my car for a couple of months now, but have not broken the 400 MPT. Yesterday I refilled with 11.95 gallons (the meter was below E and the light had been on for about 20 miles) and had 392 miles since last refill. I have an 03 (maybe 03.5, don't know how to tell) and the manual stated that the tank was 13+ gallon, not 14 though. Did they reduce the tank size? Oh and that was with 90% highway driving, with low-moderate aggressiveness and one 7 mile backup, averaging about 65 MPH excluding the jam.
Well 506 miles on a tank. Took 13.00 gallons, which was about all I could force into the filler. Was during a round trip between Boulder CO & Rocky Mountain Park and then out into Nebraska. Light had just come on. This does involve net altitude drop and maybe a tailwind, but with typical road mpg's it's really just a matter of being willing to run it down low to repeat this.
What WAS really wild was another day going through the park there. Was typically in 4th gear a third of the time with foot 80% of the way to the floor for long climb stretches. I thought the gauge was broken when it moved down real slow. Got like 44 mpg, a record for me. (Previous and subsequent fillups were also over 40, so not a fill disparity.) At average of like 8000 feet altitude with 88 F ambient. Average speed was only 35 mph or so which would help. I knew fuel injection should work OK at altitude, other than reduced peak HP due to less O2 available. But I really felt like I should have had a record LOW mileage on this stint. This P5 was going about flat out much of the time, with speed dropping almost floored in 4th. Anybody else or altitude dwellers ever see anything like that?
What WAS really wild was another day going through the park there. Was typically in 4th gear a third of the time with foot 80% of the way to the floor for long climb stretches. I thought the gauge was broken when it moved down real slow. Got like 44 mpg, a record for me. (Previous and subsequent fillups were also over 40, so not a fill disparity.) At average of like 8000 feet altitude with 88 F ambient. Average speed was only 35 mph or so which would help. I knew fuel injection should work OK at altitude, other than reduced peak HP due to less O2 available. But I really felt like I should have had a record LOW mileage on this stint. This P5 was going about flat out much of the time, with speed dropping almost floored in 4th. Anybody else or altitude dwellers ever see anything like that?
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- 2002 BJFW, 2007 BK3P, 1979 SA22C, 2005 BK3P
you're a god
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- Protege5 2003
The only way a P5 could ever get 44 mpg, at altitude, while climbing inclines, is if it was being pushed by the SUV behind it.
As for the gas gauge, it is probably not very accurate when the car is tilted substantially front to back.
I'm flattered, but really I'm just the guy doing 55 on the highway that's pissing off everyone behind me. That said, 450 miles is not a regular achievement for me. It averaged out to about 34 mpg, which is about the best gas mileage I've gotten.
The altitude results are real, and should be repeatable by others. I'm trying to formulate why. Granted, going up the mountain I was at essentially zero inches of vacuum, but since I kept it off the floor I'm thinking enrichment beyond 14.7 AFR would be small. Compare this to the typical cruising vacuum of what - 10 inches? (I have never put a road vacuum gauge on my P5 but will.) If this is true, then you're only expending like 30/20 or 150% of the level fuel usage of the flats at speed. (i.e. 3o inches of atmosphere versus 20 at 10 inch vacuum - yeah the altitude messes some with the absolute numbers, but in your favor - less air available.) The real key is going DOWN the hills. Here, you're basically shut off since modern fuel injection systems will shut off the injectors in totally unloaded decelerating conditions. So intuitively, if half the time you're using 150% and 0% the other half (i.e. the downhills) it would net to 75% of normal consumption. Again I was pulling at like 1400 RPM or so and little wind resistance at such slow speeds. My tire diameters are 7% oversized too which ups things a little.
If anyone has the patience to do it, I'm thinking cruising at 45 on the flats would also be interesting.
Google Gas Mileage in Mountains.
If anyone has the patience to do it, I'm thinking cruising at 45 on the flats would also be interesting.
Google Gas Mileage in Mountains.
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Awesome. Well done. Maybe now I don't have to attempt the 500 MPT goal myself.
450 or more MPT leader board becomes:
506 RABID_MP5
492 Dparks7
460+ Mike R.
452.6 kingal3
450 (approximate) slavrenz
not only that, your fuel pump will over heat or will at least cause unnecessary stress to your components in the tank.
my gas/millage log for the protege5
100% city driving, 85% rush hour traffic 5% mazda meets
using your best tank (KPT or kilometers per tank):
568.7 km (*0.621371192 mi /1 km) --> 353.37 mi (rounded)
45.458 L (*1 gal / 3.78541178 L) --> 12.01 gal (rounded)
which gets you your stated 29.43 mpg
these are impressive numbers for city driving. keep up the good work. your "Theoretical Max Distance" does not indicate a unit of measure, but seems reasonable to me that they are in km.
i bet if you got some time on an open highway or freeway, you'd achieve spectacular MPT numbers.
updated the picture
the theoretical max is based on my average consumption in that filling period and the 55L tank the protege5 has as a constant. meaning if i drove at the average MPG and consumed ALL of the 55L of fuel i would get the number stated. (running your tank dry is bad)
also the best was the 30MPG in the city farther down the list
also some things to consider,
mods to help gas millage are intake, carbon hood, removed stupid things like the spare tire and jack, tires with less rolling resistance, higher tire pressure (36PSI all around), knowing how to shift, coasting down hills, running red lights when necessary, not stopping for anything, taking corners and turn offs at over 120kph
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excellent.
also the best was the 30MPG in the city farther down the list
I saw that, but I was focusing on the fill up with the greatest distance traveled.
haha.
