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Whats up y'all. I bought a q50 2014 with 65k miles on it. The car drives smooth but I get shitty MPG. My average MPG is 12-14, I know most q50 owners usually get avg 17-26 MPH, that's why I'm a bit concerned. I always put premium plus gas, run with a ARK catback and drive pretty aggressive. I live in the city and look for parking for hours. Regardless, is there anything that I can do to increase my MPG? Maybe replace spark plugs or such?? Anybody has tuned their car for better MPG? Any help will be appreciated. Thank you!
 

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What's the mileage on your car? What's the tire pressure like in your wheels? When was your last alignment?
Tire psi range from 30-32.
It’s on 68000 mileage right now.
I am not sure about alignment, I haven't felt the need.
 

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At 65K miles you may get 1-2 MPG out of changing out your spark plugs, typically those are good until 85-100K miles. What type of oil do you put in? Where are you located?
If it doesn't get very hot in your area you can try running a thinner oil like 0W20 or 0W30.

With that said around 12-14 mpg for aggressive city driving is about what to expect from the 3.7L engine, the low speed stuff kills her fuel economy.
On the highway 25-27mpg should be totally doable.
 

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30-32 PSI? Sounds low to me.
 

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In my 2018 AWD RS I run 35.5-36 front and 34-34.5.5 rear with 255's all 4 corners. COLD.. 255's have a higher load capacity than the OEM 245's. At 35 rear the middle wore out faster so is to much.
 

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I run ( cold tire ) 35 with nitrogen in tires in South Florida weather. If i have to add regular air I run 33 because the expansion rate I greater air vs nitrogen. I'm not a huge fan of nitrogen, but the dealer always tops them off when they wash it. My wife gets 21.3 in town and 30-31 highway mpg. The most important thing to remember is fuel mileage is always relative to the right foot action. Heavy traffic on the Highway no cruise control is better than the automatic voodoo mode for mileage.
 

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Is there a question? If I do a lot of freeway, I average 27. Regular, mixed city/freeway, I average 24.
 

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I run ( cold tire ) 35 with nitrogen in tires in South Florida weather. If i have to add regular air I run 33 because the expansion rate I greater air vs nitrogen. I'm not a huge fan of nitrogen, but the dealer always tops them off when they wash it. My wife gets 21.3 in town and 30-31 highway mpg. The most important thing to remember is fuel mileage is always relative to the right foot action. Heavy traffic on the Highway no cruise control is better than the automatic voodoo mode for mileage.
As far as expansion rates for N2 and air, they are essentially the same since air is about 80% N2. What makes a difference is the amount of water vapor in the air when it is introduced into the tire. N2 is dry (if a dryer is used on the N2 separator, anyway) and unless the compressed air is dried (which it usually is not) then the water vapor inside the tire will expand as the tire heats and the pressure will rise higher than an N2 inflated tire. If the compressed air source is dried, then there is essentially no difference.

N2 was initially used in tires in high temperature applications and where there was a risk of fire (racing tires, military tires, aircraft tires). N2 is inert and won't contribute to a fire like an air-filled tire can if it explodes.

Even though oxygen has a higher molecular weight than nitrogen, the size of a N2 molecule is actually larger than an O2 molecule. Testing has shown that N2-inflated tires leak at a slightly lower rate than air-inflated tires because of the molecular size difference.

To take full advantage of N2's properties, the tires should be purged so that as much of the air that resides in the tire is displaced by N2. Subsequent topping of an N2 inflated tire with air basically defeats the purpose as you are introducing water vapor to the N2 again.

If you have access to free N2 to fill your tires, then by all means do so. If it costs money to fill your tires with N2, then buying a good tire gauge and routine monitoring of your tire pressures is just as effective IMHO.
 

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As far as expansion rates for N2 and air, they are essentially the same since air is about 80% N2. What makes a difference is the amount of water vapor in the air when it is introduced into the tire. N2 is dry (if a dryer is used on the N2 separator, anyway) and unless the compressed air is dried (which it usually is not) then the water vapor inside the tire will expand as the tire heats and the pressure will rise higher than an N2 inflated tire. If the compressed air source is dried, then there is essentially no difference.

N2 was initially used in tires in high temperature applications and where there was a risk of fire (racing tires, military tires, aircraft tires). N2 is inert and won't contribute to a fire like an air-filled tire can if it explodes.

Even though oxygen has a higher molecular weight than nitrogen, the size of a N2 molecule is actually larger than an O2 molecule. Testing has shown that N2-inflated tires leak at a slightly lower rate than air-inflated tires because of the molecular size difference.

To take full advantage of N2's properties, the tires should be purged so that as much of the air that resides in the tire is displaced by N2. Subsequent topping of an N2 inflated tire with air basically defeats the purpose as you are introducing water vapor to the N2 again.

If you have access to free N2 to fill your tires, then by all means do so. If it costs money to fill your tires with N2, then buying a good tire gauge and routine monitoring of your tire pressures is just as effective IMHO.
So Avadis53, $30 to inflate with nitrogen is a bit much.
 

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Consumer Reports is my bible and they say filling tires with nitrogen is not worth the time or money.

Read here.
 

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So Avadis53, $30 to inflate with nitrogen is a bit much.
To each their own. I wouldn't pay what many are charging for N2 purging and top-offs. $30 to purge and fill four tires with N2 isn't too bad. I've seen places that charge $30/tire or more to do so. It's the purging procedure that is the main cost since the tire must be filled and bled several time to remove as much air as possible. I've seen places that charge $5-$7/tire to top them off. Absolutely absurd.
 

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Consumer Reports is my bible and they say filling tires with nitrogen is not worth the time or money.

Read here.
For the typical user's passenger tires, I would agree. Marketing hype by places that invested in N2 systems and are trying to make their investment back.
 

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For the typical user's passenger tires, I would agree. Marketing hype by places that invested in N2 systems and are trying to make their investment back.
Most new cars have the TPMS, systems, you can see if your tires need air, we just need to keep an eye on it.
 

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Most new cars have the TPMS, systems, you can see if your tires need air, we just need to keep an eye on it.
Agreed. It doesn't hurt to validate the TPMS readings occasionally with an accurate tire gauge though.
 

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Most new cars have the TPMS, systems, you can see if your tires need air, we just need to keep an eye on it.
Not all of them. Some "dumb" systems only call attention to severely under inflated tires and don't give out numerical readings. Our Ford just tells you when you have a low tire...not the PSI and not even which tire. The one with the screw in it was at 23 PSI...maybe a few pounds higher when it first called attention to it, but not much more than that.
 

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Not all of them. Some "dumb" systems only call attention to severely under inflated tires and don't give out numerical readings. Our Ford just tells you when you have a low tire...not the PSI and not even which tire. The one with the screw in it was at 23 PSI...maybe a few pounds higher when it first called attention to it, but not much more than that.
Two weeks ago, my kept telling me that I have a flat tire, when it was a slow leak with a nail in it.
 

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Nitrogen makes a huge difference in my sport bikes. It doesn't leak out slightly slower, it leaks out at least 3x slower. The difference in "warm up" time is night and day. It's worth every cent I paid every time I paid it. That all having been said, IMO it's a complete waste in a street car unless you're getting it for free.
 
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