G35 fuel economy
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Joined: Feb 2018
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Go find an interstate highway (relatively flat) and get up to 60-65 mph. Set the cruise control. Now navigate to the menu/screen that displays the MPG and MPH. It updates every 60 seconds, I believe. While it's displayed, reset it (lower button - hold it in for a few seconds). Now drive for 5+ miles and see what MPG it calculates. Post back with both values.
Does the '05 have a MPG readout in the instrument cluster center menu ? I have an '08 and can cycle between outside temperature, miles to empty, "live" MPG (bar graph), average trip MPG+MPH, etc. If you do, try this:
Go find an interstate highway (relatively flat) and get up to 60-65 mph. Set the cruise control. Now navigate to the menu/screen that displays the MPG and MPH. It updates every 60 seconds, I believe. While it's displayed, reset it (lower button - hold it in for a few seconds). Now drive for 5+ miles and see what MPG it calculates. Post back with both values.
Go find an interstate highway (relatively flat) and get up to 60-65 mph. Set the cruise control. Now navigate to the menu/screen that displays the MPG and MPH. It updates every 60 seconds, I believe. While it's displayed, reset it (lower button - hold it in for a few seconds). Now drive for 5+ miles and see what MPG it calculates. Post back with both values.
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Joined: Mar 2011
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From: Central NJ
Front and rear cameras, tire pressure for all four tires can display on screen,folding side view mir
Ever check your tire pressure?
Are you carrying excessive junk in your trunk?
Ever check your wheel alignment?
Do you let your vehicle idle for long periods of time such as warming up the engine before you drive off?
Over the past fifteen years I drive a few times per year from NJ to Florida and I'm on my third Infiniti.
I consistently get over 24 MPG on each fill up sometimes over 25, 26 MPG.
I've only used regular 87 octane from truck stops Pilot, Loves, and WaWa and the only time I see poor MPG around 18 is when the wife drives it in Florida making short trips to the fitness center
Telcoman
Get the vehicle up on jackstands and spin the wheels by hand with it in neutral to verify something isn't dragging.
Check your tire pressure (tpms might be malfunctioning).
Have the vehicle aligned (toe causes major friction and severely reduced mileage).
Pull and inspect the plugs, they tell you almost everything you need to know about the conditions in the combustion chamber.
Clean/replace your air filter, clean the MAF, inspect and clean the TB if necessary.
Inspect/clean the PCV valve.
OBD2 realtime scan the O2 sensors to verify they're cycling properly at idle and with throttle.
Remove/inspect the CATS with an inspection mirror or borescope for any melting on the media.
Smoke test exhaust system for leaks.
Run seafoam through the gas tank.
Perform an ECM and idle recalibration.
Check your tire pressure (tpms might be malfunctioning).
Have the vehicle aligned (toe causes major friction and severely reduced mileage).
Pull and inspect the plugs, they tell you almost everything you need to know about the conditions in the combustion chamber.
Clean/replace your air filter, clean the MAF, inspect and clean the TB if necessary.
Inspect/clean the PCV valve.
OBD2 realtime scan the O2 sensors to verify they're cycling properly at idle and with throttle.
Remove/inspect the CATS with an inspection mirror or borescope for any melting on the media.
Smoke test exhaust system for leaks.
Run seafoam through the gas tank.
Perform an ECM and idle recalibration.
ok thanks, ill do this
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Joined: Feb 2018
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I asked above, but do you fill the tank until it clicks off, drive for a while, then fill up again until it clicks off ? Then use the miles driven vs the gallons filled to calculate MPG ? If you're going by the fuel gauge, that won't be accurate (enough).
Is this a manual or automatic ? Not long ago, a member described their driving style with their manual - this person shifted at 4000 rpm. Suggested this was in every gear, driving through town stoplight to stoplight, and so on.
ive gotten and alignment, i let the car warm up, the only thing i know is ive probably hit the cats or the exhaust on a bumps a few times. also my rear tire pressure sensors are dead
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Joined: Feb 2018
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What is your tire pressure(s) ? By "warming up", the person asking was checking more along the lines of letting it warm up for 15 minutes, for example (I presume they meant something like that). If you let it warm up for ~30 seconds or a minute, it's a non-factor.
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Joined: Mar 2011
Posts: 2,605
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From: Central NJ
Front and rear cameras, tire pressure for all four tires can display on screen,folding side view mir
If you are warming up your vehicle you are killing your MPG.
Even though your rear tire TPMS are not working how often do you check the tire pressure. Why don't you replace them?
Telcoman
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From: Washington State
Coupe 6MT Premium RAS
Well warming up is also to let metal expand to it's operating limit. But that depends ENTIRELY on how you drive. I have an immediate highway merge about 30 seconds down the road so I usually have my vehicle halfway warmed before I drive.
What is your tire pressure(s) ? By "warming up", the person asking was checking more along the lines of letting it warm up for 15 minutes, for example (I presume they meant something like that). If you let it warm up for ~30 seconds or a minute, it's a non-factor.
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Joined: Mar 2011
Posts: 2,605
Likes: 197
From: Central NJ
Front and rear cameras, tire pressure for all four tires can display on screen,folding side view mir
OP is located in Florida where they wear winter coats when the temperature is 60 degrees
Telcoman
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G35x awd sedan
I got an 05 g35x completely stock with almost 100k miles and I'm averaging 15-17 mpg city/highway combined. I did just replace the crankshaft sensor and harness on the passenger side cause of a code and mpg got boosted from the 14-15 range. And I know it may seem obvious but make sure snow mode isnt on cause that will kill your mpg
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2) 5 minutes of warming up is completely unnecessary in FL. 1 minute is more than sufficient. Now, is it the cause of 12mpg vs 15-20 ? I'm skeptical. Sure is an easy way to test though, huh ? Quit warming it up for as long as you've been. Start limiting it to 30 seconds or at most, 1 minute.