Ok im really tired of my 8 being a gas guzzler
12-25-2009, 07:42 PM
#26
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Well, I have managed to get 175miles to the tank with my 09. This is like 10mpg. It has 500miles now. I hope to get better mpg, but am not complaining now because I know I am a little more spirited in this car for the time being. Redline, 100mph, of course after it warms up...
I do not drive this car everyday. When I do, it is because I want to. If i did have to drive it to work, I do not think I would fare any better. It is a short drive through more residential/city areas than not meaning stop and go. I have to go out of my way to hit the freeway which I do when I drive this car.
I knew coming in that this car is thirsty for fuel and oil. Right now I am thirsty for fun... I dont know who will give it first
. I will drive normal on my next fill up to see what I get.
I do not drive this car everyday. When I do, it is because I want to. If i did have to drive it to work, I do not think I would fare any better. It is a short drive through more residential/city areas than not meaning stop and go. I have to go out of my way to hit the freeway which I do when I drive this car.
I knew coming in that this car is thirsty for fuel and oil. Right now I am thirsty for fun... I dont know who will give it first
. I will drive normal on my next fill up to see what I get.
12-25-2009, 08:41 PM
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Thanks... You all are right... It was just a couple of times... Feel really bad now and very silly. I will do better. Hard not to, but will pay in the end if i am careless now 
Merry Christmas to me...
Merry Christmas to me...
12-25-2009, 09:59 PM
#31
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Ok so 2 months ago I got my 04 rx8 with 80000km from a dealer. Bought extended warranty. I also bought new plugs, coils, wires, K&N drop in filter, cleaned MAF sensor and reset e-shaft with the 20 brake pedal trick. All that was done at 81000km.
Now I gave it some time that maybe the ECU needs to relearn fuel trims. But this is completely ridiculous im doing 300km per full to the top gas tank. I got 320km once and I was like woahhh.
Thats 185 miles per tank for you americans. My daily drive is 1km to the highway and 24km on the highway once I hit work. 5 days a week. I am not an agressive driver, I redline once or twice a day if not im always in the 3500rpm while cruising.
Im pretty sure there is def something wrong with the car. Any ideas? I mean 20L/100km is not anything near what mazda advertised. The car now has 83500km.
Im pretty sure the car was never seafoamed, would that be a solution? or improve mileage?
My leading plugs were black with brown crust around the tips and the trailing were the same but less black and more brown.
What could be wrong? I knew when I got the 8 it would be around 12-15L/100km not freakn 20.
Now I gave it some time that maybe the ECU needs to relearn fuel trims. But this is completely ridiculous im doing 300km per full to the top gas tank. I got 320km once and I was like woahhh.
Thats 185 miles per tank for you americans. My daily drive is 1km to the highway and 24km on the highway once I hit work. 5 days a week. I am not an agressive driver, I redline once or twice a day if not im always in the 3500rpm while cruising.
Im pretty sure there is def something wrong with the car. Any ideas? I mean 20L/100km is not anything near what mazda advertised. The car now has 83500km.
Im pretty sure the car was never seafoamed, would that be a solution? or improve mileage?
My leading plugs were black with brown crust around the tips and the trailing were the same but less black and more brown.
What could be wrong? I knew when I got the 8 it would be around 12-15L/100km not freakn 20.
I'm under 40k km and changed the plugs, still have to change the coils (bought them, still on a shelf).
Try seafoaming it, but I dont know if it's advised during winter :X
12-25-2009, 10:29 PM
#32
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I'd contend that your car is not in peak health either then.
Don't judge "fine" as being equal to your car, when better is clearly possible. True, he has the option of just "dealing with it", as you are, but he also has the option of working on it to restore the health of his 8.
Don't judge "fine" as being equal to your car, when better is clearly possible. True, he has the option of just "dealing with it", as you are, but he also has the option of working on it to restore the health of his 8.
that being said, my bad, i reread the original post and my situation is the opposite, i do 90% city driving. and the OP is matching my mileage. i get the average 20ish highway.
12-26-2009, 01:36 AM
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thanks for the multiple replies guys!
Actually I like my car to be a peak performance and healthy at all times. For God's sake I wash her more than I wash myself! (hahaha joke obviously!)
I think I will bring it to the dealer after the holidays and force them to do something about it. Maybe the nasty smell that invades my garage after my 30 mins drive from work has something to do with my bad mileage. Kinda weird cause the new CAT dates from july 09. How can it fail so early... Unless mazda builds terrible quality car parts.
Actually I like my car to be a peak performance and healthy at all times. For God's sake I wash her more than I wash myself! (hahaha joke obviously!)
I think I will bring it to the dealer after the holidays and force them to do something about it. Maybe the nasty smell that invades my garage after my 30 mins drive from work has something to do with my bad mileage. Kinda weird cause the new CAT dates from july 09. How can it fail so early... Unless mazda builds terrible quality car parts.
12-26-2009, 01:43 AM
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theres nothing wrong with his car, and if there is, the mileage will only improve slightly. That is the regular mileage of a car, and for the people who say they are getting 600, i don't know. It just sounds unbelievable that someones car could do 2x better than most people?
I think there is something in addition to "inherent design characteristics" contributing to the poor fuel mileage, either driving habits, mechanical issues, or both. I have a 2009 with only 3,000 miles on it, so it may not even be fully broken in yet. Yet on my daily commute round-trip, which is 10 miles of city and 36 miles freeway, I am consistently getting 23-24 mpg. For the holiday I just drove freeways for 200 miles between 75-80 mph, and it used a little over half a tank, so obviously doing better than my usual commute. I'll know the exact figure when I fill up tomorrow.
The cars will definitely pull mid-20s mpg if they are mechanically sound and driven reasonably.
(keep in mind I'm quoting miles, not kilometers)
Last edited by PeteInLongBeach; 12-26-2009 at 01:50 AM.
12-26-2009, 02:19 AM
#37
+1 for getting the cat looked at. Also, make sure the car had all its recalls/TSBs for ECU firmware reflashes.. the earlier ones run richer, apparently. I'm in Montreal also, my average fuel mileage in sig.. been tracking since about Oct. It's an 04 also. About 370km to the light, mixed highway/traffic. What speed are you going on the highway? I noticed you get about 24mpg at 100, but only like 18 at 130. I need to do more long highway trips to have enough stats, but over a couple of trips to Ottawa that's what it works out to.
Yeah bad smells can be cat-related. Can you describe the smell? The cat itself is as reliable as any other car's cat, but in these cars if the coilpacks go, the amount of unburnt fuel going into the cat increases and the thing dies quickly, even a brand new cat. You said you had those things replaced? Make sure the work was actually done maybe.. who knows.
thanks for the multiple replies guys!
Actually I like my car to be a peak performance and healthy at all times. For God's sake I wash her more than I wash myself! (hahaha joke obviously!)
I think I will bring it to the dealer after the holidays and force them to do something about it. Maybe the nasty smell that invades my garage after my 30 mins drive from work has something to do with my bad mileage. Kinda weird cause the new CAT dates from july 09. How can it fail so early... Unless mazda builds terrible quality car parts.
Actually I like my car to be a peak performance and healthy at all times. For God's sake I wash her more than I wash myself! (hahaha joke obviously!)
I think I will bring it to the dealer after the holidays and force them to do something about it. Maybe the nasty smell that invades my garage after my 30 mins drive from work has something to do with my bad mileage. Kinda weird cause the new CAT dates from july 09. How can it fail so early... Unless mazda builds terrible quality car parts.
Yeah bad smells can be cat-related. Can you describe the smell? The cat itself is as reliable as any other car's cat, but in these cars if the coilpacks go, the amount of unburnt fuel going into the cat increases and the thing dies quickly, even a brand new cat. You said you had those things replaced? Make sure the work was actually done maybe.. who knows.
Last edited by Loki; 12-26-2009 at 02:26 AM.
12-26-2009, 02:39 AM
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+1 for getting the cat looked at. Also, make sure the car had all its recalls/TSBs for ECU firmware reflashes.. the earlier ones run richer, apparently. I'm in Montreal also, my average fuel mileage in sig.. been tracking since about Oct. It's an 04 also. About 370km to the light, mixed highway/traffic. What speed are you going on the highway? I noticed you get about 24mpg at 100, but only like 18 at 130. I need to do more long highway trips to have enough stats, but over a couple of trips to Ottawa that's what it works out to.
Yeah bad smells can be cat-related. Can you describe the smell? The cat itself is as reliable as any other car's cat, but in these cars if the coilpacks go, the amount of unburnt fuel going into the cat increases and the thing dies quickly, even a brand new cat. You said you had those things replaced? Make sure the work was actually done maybe.. who knows.
Yeah bad smells can be cat-related. Can you describe the smell? The cat itself is as reliable as any other car's cat, but in these cars if the coilpacks go, the amount of unburnt fuel going into the cat increases and the thing dies quickly, even a brand new cat. You said you had those things replaced? Make sure the work was actually done maybe.. who knows.
I drive around 110-120 km/h on the highway
As for the smell it is like a burnt rubber kind of smell or like weird plastic i dunno. I heard rotten egg smell is a bad CAT but ive never had rotten eggs for breakfast so im not sure what it smells like. I will cook eggs tomorrow and let them rot for a week or so and compare the smells.
12-26-2009, 02:49 AM
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definitely get your cat checked.
My cat is bad (been working on getting it off most of Christmas day, more this morning in a couple hours), my mileage went from 17-22 down to ~9. The only smell that I smell is a burnt plastic/rubber smell, from stuff around the cat heating up and melting.
Most cars the cat starts smelling like rotten eggs, but I've never heard of that smell with a rotary. I think our exhaust gas temp is so hot usually we start frying surrounding materials outside the cat, and the rotten smell is probably burnt out or overwhelmed or something.
When your cat has reached critical failure, as mine has, it will be a serious amount of trouble to maintain highway speed. I can have the pedal to the floor in 3rd gear and it simply can't breath enough to get over 74mph @7500rpm. In 6th, I can't accelerate with anything short of the pedal to the floor, anything less I start losing speed. (Accompanied by the whiff of rubber/plastic smoke, exterior cat temp over 400 degrees, etc...). I have brand new coils, plugs, air filter, cleaned MAF, and reset e-shaft sensor, all which failed to restore my power loss. If it isn't my cat, it is my compression, but WOT under 4k rpm feels perfectly normal, so I don't think it's compression.
If you run into that, get the RPMs low fast, and crawl home or to a dealer or a shop, because you are on the edge of causing engine damage in the strain, backwash of exhaust, etc...
My cat is bad (been working on getting it off most of Christmas day, more this morning in a couple hours), my mileage went from 17-22 down to ~9. The only smell that I smell is a burnt plastic/rubber smell, from stuff around the cat heating up and melting.
Most cars the cat starts smelling like rotten eggs, but I've never heard of that smell with a rotary. I think our exhaust gas temp is so hot usually we start frying surrounding materials outside the cat, and the rotten smell is probably burnt out or overwhelmed or something.
When your cat has reached critical failure, as mine has, it will be a serious amount of trouble to maintain highway speed. I can have the pedal to the floor in 3rd gear and it simply can't breath enough to get over 74mph @7500rpm. In 6th, I can't accelerate with anything short of the pedal to the floor, anything less I start losing speed. (Accompanied by the whiff of rubber/plastic smoke, exterior cat temp over 400 degrees, etc...). I have brand new coils, plugs, air filter, cleaned MAF, and reset e-shaft sensor, all which failed to restore my power loss. If it isn't my cat, it is my compression, but WOT under 4k rpm feels perfectly normal, so I don't think it's compression.
If you run into that, get the RPMs low fast, and crawl home or to a dealer or a shop, because you are on the edge of causing engine damage in the strain, backwash of exhaust, etc...
Last edited by RIWWP; 12-26-2009 at 02:51 AM.
12-26-2009, 05:28 PM
#40
So the cat was changed earlier in the year, but the coilpacks just recently, when you bought the car? If the previous owner drove around with bad coilpacks he could've killed his brand new cat and let you inherit the problem:\
Rotten eggs smell like sulfur... if you've ever smelled a natural gas leak, it's that smell.
Rotten eggs smell like sulfur... if you've ever smelled a natural gas leak, it's that smell.
12-27-2009, 12:28 AM
#41
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definitely get your cat checked.
My cat is bad (been working on getting it off most of Christmas day, more this morning in a couple hours), my mileage went from 17-22 down to ~9. The only smell that I smell is a burnt plastic/rubber smell, from stuff around the cat heating up and melting.
Most cars the cat starts smelling like rotten eggs, but I've never heard of that smell with a rotary. I think our exhaust gas temp is so hot usually we start frying surrounding materials outside the cat, and the rotten smell is probably burnt out or overwhelmed or something.
When your cat has reached critical failure, as mine has, it will be a serious amount of trouble to maintain highway speed. I can have the pedal to the floor in 3rd gear and it simply can't breath enough to get over 74mph @7500rpm. In 6th, I can't accelerate with anything short of the pedal to the floor, anything less I start losing speed. (Accompanied by the whiff of rubber/plastic smoke, exterior cat temp over 400 degrees, etc...). I have brand new coils, plugs, air filter, cleaned MAF, and reset e-shaft sensor, all which failed to restore my power loss. If it isn't my cat, it is my compression, but WOT under 4k rpm feels perfectly normal, so I don't think it's compression.
If you run into that, get the RPMs low fast, and crawl home or to a dealer or a shop, because you are on the edge of causing engine damage in the strain, backwash of exhaust, etc...
My cat is bad (been working on getting it off most of Christmas day, more this morning in a couple hours), my mileage went from 17-22 down to ~9. The only smell that I smell is a burnt plastic/rubber smell, from stuff around the cat heating up and melting.
Most cars the cat starts smelling like rotten eggs, but I've never heard of that smell with a rotary. I think our exhaust gas temp is so hot usually we start frying surrounding materials outside the cat, and the rotten smell is probably burnt out or overwhelmed or something.
When your cat has reached critical failure, as mine has, it will be a serious amount of trouble to maintain highway speed. I can have the pedal to the floor in 3rd gear and it simply can't breath enough to get over 74mph @7500rpm. In 6th, I can't accelerate with anything short of the pedal to the floor, anything less I start losing speed. (Accompanied by the whiff of rubber/plastic smoke, exterior cat temp over 400 degrees, etc...). I have brand new coils, plugs, air filter, cleaned MAF, and reset e-shaft sensor, all which failed to restore my power loss. If it isn't my cat, it is my compression, but WOT under 4k rpm feels perfectly normal, so I don't think it's compression.
If you run into that, get the RPMs low fast, and crawl home or to a dealer or a shop, because you are on the edge of causing engine damage in the strain, backwash of exhaust, etc...
and yes the CAT was changed in july 09 and I bought the car in october. I changed everything right away myself.
One last important question: When the dealer changes a bad CAT are they suppose to like reflash the ECU or something? Because the engine goes into protection mode if im not mistaken correct?
Last edited by djfa; 12-27-2009 at 12:31 AM.
12-27-2009, 01:14 PM
#42
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holy smokes that is great advice. Exactly what im going through. I will take it to the dealer after the holidays.
and yes the CAT was changed in july 09 and I bought the car in october. I changed everything right away myself.
One last important question: When the dealer changes a bad CAT are they suppose to like reflash the ECU or something? Because the engine goes into protection mode if im not mistaken correct?
and yes the CAT was changed in july 09 and I bought the car in october. I changed everything right away myself.
One last important question: When the dealer changes a bad CAT are they suppose to like reflash the ECU or something? Because the engine goes into protection mode if im not mistaken correct?
As a follow up though, When I removed the cat and put on the midpipe, I was at 1 tick under half a tank, at 68 miles on the trip. As soon as I finished doing the pipe swap, I left on a 10hr trip, and I filled up the first time at 212 miles on the trip, 13.4 gallons. So I went from ~68 miles on the first half to 144 miles on the second half.
I got serious for a tank, and got 345 miles on the tank, then decided it was too boring so stomped on it as I found opportunity, and my next tank was 290 miles on 14.1 gallons.
(all yesterday and this morning, RI to Ohio, basically all highway)
12-27-2009, 01:22 PM
#43
You can reset everything yourself without issue. No reflash is needed.
As a follow up though, When I removed the cat and put on the midpipe, I was at 1 tick under half a tank, at 68 miles on the trip. As soon as I finished doing the pipe swap, I left on a 10hr trip, and I filled up the first time at 212 miles on the trip, 13.4 gallons. So I went from ~68 miles on the first half to 144 miles on the second half.
I got serious for a tank, and got 345 miles on the tank, then decided it was too boring so stomped on it as I found opportunity, and my next tank was 290 miles on 14.1 gallons.
(all yesterday and this morning, RI to Ohio, basically all highway)
As a follow up though, When I removed the cat and put on the midpipe, I was at 1 tick under half a tank, at 68 miles on the trip. As soon as I finished doing the pipe swap, I left on a 10hr trip, and I filled up the first time at 212 miles on the trip, 13.4 gallons. So I went from ~68 miles on the first half to 144 miles on the second half.
I got serious for a tank, and got 345 miles on the tank, then decided it was too boring so stomped on it as I found opportunity, and my next tank was 290 miles on 14.1 gallons.
(all yesterday and this morning, RI to Ohio, basically all highway)
12-27-2009, 03:04 PM
#44
Wow, even my worst mileage, all city and punching it, is always over 320km per tank (~200mi). My best (all highway and babying it without using AC) is closer to 620km per tank (~390mi). '07, 6MT, 12,000mi.
Something is wrong if you're only getting a piece of that.
Something is wrong if you're only getting a piece of that.
12-28-2009, 09:05 AM
#45
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Here is a pic of my cat that is caused the drop in mileage from 18-22 down to 9.
The chunks are the front honeycomb, and there isn't enough material laying there to make up the front one, so I assume the remainder is particulate matter packed into the 2nd honeycomb.
The chunks are the front honeycomb, and there isn't enough material laying there to make up the front one, so I assume the remainder is particulate matter packed into the 2nd honeycomb.
01-22-2010, 04:53 PM
#46
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My new '09 R3, just turned 1400 miles and so far the best I've got is about 19mpg, 95% hwy. and granny driving most of the time.
Avg. 17, I hope warmer weather brings a little increase.. 400 a month for gas will get expensive. Last tank went to 247miles. I remember my '04 got right about the same though.
You would think as smart as some people are someone would come up with a way to pull more MPG from these motors.
Avg. 17, I hope warmer weather brings a little increase.. 400 a month for gas will get expensive. Last tank went to 247miles. I remember my '04 got right about the same though.
You would think as smart as some people are someone would come up with a way to pull more MPG from these motors.
01-22-2010, 05:04 PM
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The big engines that make big power also have enough torque down load to lug the weight around. We don't have torque low, so they have to gear up to increase where we sit in the revs, and this is one thing that drops the max mileage.
The other thing to consider is that you are pulling ~186hp per liter. Pretend you have a small block v8 (what, 4.2L? I don't know my v8s) pulling 186hp per liter. That's 781hp. Any v8 with that much power has far worse gas mileage than we do. A 3.6L V6 with 186hp per liter would be 669hp. Again, worse mileage than we have.
Look at the bright side, it should be worse. Get a beater and break even in 2.5 months from gas savings.
The other thing to consider is that you are pulling ~186hp per liter. Pretend you have a small block v8 (what, 4.2L? I don't know my v8s) pulling 186hp per liter. That's 781hp. Any v8 with that much power has far worse gas mileage than we do. A 3.6L V6 with 186hp per liter would be 669hp. Again, worse mileage than we have.
Look at the bright side, it should be worse. Get a beater and break even in 2.5 months from gas savings.
