bad gas mileage
11-11-2009, 05:05 AM
#16
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Here is an accurate way to calculate gas mileage.
1. Go to your favorite gas station.
2. Pump gas, noting the notch that you selected for fuel delivery rate. Some pumps have two notches. Valero usually has three notches. Also, remember the pump you used.
3. Let it fill the tank completely and click off by itself. Don't add any more gas.
4. Reset your trip odometer to zero.
5. Drive the car in your normal style until the tank is near empty.
6. Go back to the same gas station and go back to the same pump.
7. Pump gas using the same notch (delivery rate) you selected before.
8. Let it fill the tank completely and click off by itself. Don't add any more gas.
9. Divide the mileage from your trip odometer by the number of gallons you pumped.
10. You now have your MPG.
1. Go to your favorite gas station.
2. Pump gas, noting the notch that you selected for fuel delivery rate. Some pumps have two notches. Valero usually has three notches. Also, remember the pump you used.
3. Let it fill the tank completely and click off by itself. Don't add any more gas.
4. Reset your trip odometer to zero.
5. Drive the car in your normal style until the tank is near empty.
6. Go back to the same gas station and go back to the same pump.
7. Pump gas using the same notch (delivery rate) you selected before.
8. Let it fill the tank completely and click off by itself. Don't add any more gas.
9. Divide the mileage from your trip odometer by the number of gallons you pumped.
10. You now have your MPG.
I haven't really had the chance to do that test, I rarely fill up the tank to full because don't got money at the moment. However, I was able to get a hold of the Cobb AP Version 2 and I checked my air/fuel ratio. Everything seems normal on that. Also I'm boosting 15 PSI holding about 12-13ish. I set the access port to a program where it moniters your average gas milage MPG. It came out to show 12.9 MPG which is AMAZINGLY terrible. I'm going to re-do the test again tomorrow while going to school. It doesn't make sense because while I was driving the car normally it was showing I get 47 MPG (that's driving about 40-50 in 4th gear). I'll get back to you all and let you know how the 2nd test went.
Also, what I was thinking it MIGHT be is the tune I'm running. I'm running stage 1 with the Cobb Tuner version 1. However, I'm not running the Stage 1 California/Arizona map, because my AP didn't come with that one. So I loaded the (I think) Nevada/Washington one...(or some other state that I'm mixing up). Do you guys think that would have anything to do with it?
Thanks for all your guys' help so far though. This problem though is eating my wallet alive though
11-11-2009, 09:48 AM
#17
I haven't really had the chance to do that test, I rarely fill up the tank to full because don't got money at the moment. However, I was able to get a hold of the Cobb AP Version 2 and I checked my air/fuel ratio. Everything seems normal on that. Also I'm boosting 15 PSI holding about 12-13ish. I set the access port to a program where it moniters your average gas milage MPG. It came out to show 12.9 MPG which is AMAZINGLY terrible. I'm going to re-do the test again tomorrow while going to school. It doesn't make sense because while I was driving the car normally it was showing I get 47 MPG (that's driving about 40-50 in 4th gear). I'll get back to you all and let you know how the 2nd test went.
Also, what I was thinking it MIGHT be is the tune I'm running. I'm running stage 1 with the Cobb Tuner version 1. However, I'm not running the Stage 1 California/Arizona map, because my AP didn't come with that one. So I loaded the (I think) Nevada/Washington one...(or some other state that I'm mixing up). Do you guys think that would have anything to do with it?
Thanks for all your guys' help so far though. This problem though is eating my wallet alive though
Also, what I was thinking it MIGHT be is the tune I'm running. I'm running stage 1 with the Cobb Tuner version 1. However, I'm not running the Stage 1 California/Arizona map, because my AP didn't come with that one. So I loaded the (I think) Nevada/Washington one...(or some other state that I'm mixing up). Do you guys think that would have anything to do with it?
Thanks for all your guys' help so far though. This problem though is eating my wallet alive though
Do you have a boost gauge?
It takes more gas when you boost, I try to stay out of boost unless im getting onto the freeway or something.
Im getting 20-22 mpg depending on how I drive. Usually right around 300miles per tank give or take.
11-13-2009, 04:31 PM
#18
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They have different type of gas, and prolly not a good idea to have that map loaded.
Do you have a boost gauge?
It takes more gas when you boost, I try to stay out of boost unless im getting onto the freeway or something.
Im getting 20-22 mpg depending on how I drive. Usually right around 300miles per tank give or take.
Do you have a boost gauge?
It takes more gas when you boost, I try to stay out of boost unless im getting onto the freeway or something.
Im getting 20-22 mpg depending on how I drive. Usually right around 300miles per tank give or take.
Well I borrowed my friends AP version 1. In the city, average I'm getting is 16.9 miles, and on the freeway my average is 21.6
Those are the numbers that came out after I did the fuel economy test. Yeah the only time I boost is when I'm getting onto the free way or trying to pass a car. But those numbers are terrible! I should be getting at least 21 in the city and 26 in the freeway, correct me if I'm wrong.
11-13-2009, 05:14 PM
#19
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You really need to follow my 10 steps to get an accurate number. 
While you can go by the readings from the AP, they won't tell you the average MPG you're getting out of a tank. I suggest that you save your money and pump a full tank of gas.
Is your maintenance up to date? It can make a difference. When I was at 118k, I averaged 22-23 mpg. When I did the 120k service, it went up to 24 mpg. I drive 67% hwy and 33% city. I don't have a lead foot unless traffic is light and I feel like having a bit of fun. My car is mostly stock... until I save some more money.
While you can go by the readings from the AP, they won't tell you the average MPG you're getting out of a tank. I suggest that you save your money and pump a full tank of gas.
Is your maintenance up to date? It can make a difference. When I was at 118k, I averaged 22-23 mpg. When I did the 120k service, it went up to 24 mpg. I drive 67% hwy and 33% city. I don't have a lead foot unless traffic is light and I feel like having a bit of fun. My car is mostly stock... until I save some more money.
11-14-2009, 05:02 PM
#23
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You really need to follow my 10 steps to get an accurate number.
While you can go by the readings from the AP, they won't tell you the average MPG you're getting out of a tank. I suggest that you save your money and pump a full tank of gas.
Is your maintenance up to date? It can make a difference. When I was at 118k, I averaged 22-23 mpg. When I did the 120k service, it went up to 24 mpg. I drive 67% hwy and 33% city. I don't have a lead foot unless traffic is light and I feel like having a bit of fun. My car is mostly stock... until I save some more money.
While you can go by the readings from the AP, they won't tell you the average MPG you're getting out of a tank. I suggest that you save your money and pump a full tank of gas.
Is your maintenance up to date? It can make a difference. When I was at 118k, I averaged 22-23 mpg. When I did the 120k service, it went up to 24 mpg. I drive 67% hwy and 33% city. I don't have a lead foot unless traffic is light and I feel like having a bit of fun. My car is mostly stock... until I save some more money.
Yeah you're absolutely correct, my dads been telling me the same but I don't have the money for a full tank. But that's my test I'm waiting to do, I was just seeing if there's any other reason.
Also, I was looking into changing my Stage 1 map to the Arizona/California/Nevada map because the map I'm running now is a different state so maybe different fuel quality? But the problem is, I have the Cobb AP version 1 and I can't figure out how to plug it into my computer and sync a map. The only thing my AP came with (used) is the plug itself that plugs into the ECU and AP, and an AC adapter...which plugs into a wall outlet and into the access port. There's no addition cables or wires that plug into a PC.
Are you or anyone familiar with this or know where I can get that's needed? I looked up Cobbtuning.com but everything is Version 2 not 1.
11-15-2009, 04:58 PM
#24
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I'm not familiar with the V1 AP. But the V2 is nice to work with. 
I'd give Cobb's tech support a call. They should be able to tell you how to get an AZ/CA/NV map. Yeah, our gas is **** poor compared to the rest of the country, so we get a "special" map. East Coast and Midwest states get 93 octane.
I'd give Cobb's tech support a call. They should be able to tell you how to get an AZ/CA/NV map. Yeah, our gas is **** poor compared to the rest of the country, so we get a "special" map. East Coast and Midwest states get 93 octane.
11-16-2009, 02:34 AM
#25
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alright will do. yeah i was looking at the V2 when i was barrowing it. very very easy to work with. and its so nice and small/compact. the V1 feels like a brick.
11-18-2009, 05:16 PM
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You cant really go off the ap MPG estimates while neat to look at your trip odomoter / number of gallons is going to be your best bet but you cant really tell unless you are working off a full tank and at that you need to do it twice.
Maintenance is usually going to be the cause of a car getting good mpg going to bad mpg. Check air filter and replace plugs if its time. Air filter is $8 and cant hurt.
Maintenance is usually going to be the cause of a car getting good mpg going to bad mpg. Check air filter and replace plugs if its time. Air filter is $8 and cant hurt.
11-20-2009, 05:13 AM
#29
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You cant really go off the ap MPG estimates while neat to look at your trip odomoter / number of gallons is going to be your best bet but you cant really tell unless you are working off a full tank and at that you need to do it twice.
Maintenance is usually going to be the cause of a car getting good mpg going to bad mpg. Check air filter and replace plugs if its time. Air filter is $8 and cant hurt.
Maintenance is usually going to be the cause of a car getting good mpg going to bad mpg. Check air filter and replace plugs if its time. Air filter is $8 and cant hurt.
how can you tell it's time to change the spark plugs? only problem with changing them is it's placed in a terrible area. but you gotta do what you gotta do. and the air filter...i have the SPT intake. Can i just clean that out or do i have to buy a new SPT filter.