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fuel problem

Old 01-24-2013, 11:01 AM
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fuel problem

I have 2007 6 forward rx8
no mods
mileage is 24000 kms
it gives me 12 mpg when driving like a grandma!
the car starts with in a second whether cold or hot!
runs smooth infact its a bullet!
what could be the problem?i mean is it normal?
compression also fine!
Old 01-24-2013, 11:13 AM
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Well that's odd!
Old 01-24-2013, 11:19 AM
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Originally Posted by TopGear8
Well that's odd!
does the car need tunning?
Old 01-24-2013, 11:48 AM
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there is no tuning, the ECU automatically adjusts fuel trims according to various sensors on the engine and in the exhaust.

check your fuel pump for leakage, and if that is city only mileage it is rather normal.
Old 01-24-2013, 12:02 PM
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Originally Posted by Karack
there is no tuning, the ECU automatically adjusts fuel trims according to various sensors on the engine and in the exhaust.

check your fuel pump for leakage, and if that is city only mileage it is rather normal.
well its only city driving
Old 01-24-2013, 12:06 PM
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then i would just drive the car. city mileage varies greatly and there is no solid rule of thumb for city mileage, due to congestion and the actual distance between stops and amount of time sitting idling before moving again. rotaries in general get horrible city mileage and even highway they are considered very poor.

you could try cleaning the MAF sensor, replacing the plugs/wires/coils and front O2 sensor to maybe gain 1-2mpg back but for the cost you would be taking 2 steps backwards in saving money on gas. (cost approximately $500usd which would take years to recoup even if mileage stays up).

Last edited by Karack; 01-24-2013 at 12:11 PM.
Old 01-24-2013, 04:13 PM
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driving like a granny. thats your problem.
believe it or not. mid range rpm is more efficient than low rpm.
keep the rpm around 3-4k.
also pump the tires up to 35psi will get better gas millage.
Old 01-24-2013, 09:48 PM
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Originally Posted by Ayan
I have 2007 6 forward rx8

Do you have a 6 too?
Old 01-25-2013, 11:03 AM
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Originally Posted by jasonrxeight
driving like a granny. thats your problem.
believe it or not. mid range rpm is more efficient than low rpm.
keep the rpm around 3-4k.
also pump the tires up to 35psi will get better gas millage.
Sorry I do not mean to hijack this thread, I have a question.

Could you please elaborate on that more? I was also curious about such things as I've owned an rx8 for 1 1/2 months now. There are times where I am at 50-60 miles in 6th gear and then there will be times when I will be in a lower gear to keep rpms high.

I understand the daily redline routine and spirited driving keeps the engine healthy. But for driving in the city at about 50-60km, which gear would best fit mileage if you say mid range rpm is more efficient? I can be in any gear from 3rd to 6th in city speeds.

Lately I just stick to 4th gear for city driving at roughly 50-60 Km/h.
Old 01-25-2013, 09:58 PM
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Originally Posted by khaira93
Sorry I do not mean to hijack this thread, I have a question.

Could you please elaborate on that more? I was also curious about such things as I've owned an rx8 for 1 1/2 months now. There are times where I am at 50-60 miles in 6th gear and then there will be times when I will be in a lower gear to keep rpms high.

I understand the daily redline routine and spirited driving keeps the engine healthy. But for driving in the city at about 50-60km, which gear would best fit mileage if you say mid range rpm is more efficient? I can be in any gear from 3rd to 6th in city speeds.

Lately I just stick to 4th gear for city driving at roughly 50-60 Km/h.
like I said no lower than 3000 rpm for best efficiency.
the problem is at low rpm the spark plug holes are causing compression loss as the apex seals swipe across them. higher rpm meaning the rotor is spinning faster so less compression loss.

Last edited by jasonrxeight; 01-26-2013 at 12:04 PM.
Old 01-25-2013, 10:13 PM
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Originally Posted by monchie
Do you have a 6 too?
different terms for different locales.

6 forward gears, manual in other words.
Old 01-26-2013, 04:05 PM
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Originally Posted by Karack
different terms for different locales.

6 forward gears, manual in other words.

Now i know...
Old 01-26-2013, 09:54 PM
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He's (the OP) is from Pakistan.
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