Mileage improvements need suggestions...

[pcowner]

What would you guys recommend to improve gas mileage, I'm getting 11-12 in a city, gentle driving? I have 09 LT, 135K

 

[08HoeCD]

I get just under 15mpg with mostly city driving in my '08 with 133K miles.

If it's 4wd, keep her in 2wd only; proper air pressure in all tires; check for clean air filter, maf and throttle body. These are the basics, of course. I don't believe in spending hundreds of dollars on exhaust, intake, tuners, etc. to get another 2mpg in fuel efficiency----that's like spending a dollar to save a dime.

 

[massivespl]

I get just under 15mpg with mostly city driving in my '08 with 133K miles.

If it's 4wd, keep her in 2wd only; proper air pressure in all tires; check for clean air filter, maf and throttle body. These are the basics, of course. I don't believe in spending hundreds of dollars on exhaust, intake, tuners, etc. to get another 2mpg in fuel efficiency----that's like spending a dollar to save a dime.

Cold air intake is like $80 on eBay. Over the coarse of a year it will pay for itself. That's like spending a dime and getting a dollar.

 

[Jason_S]

Want good MPGs? Buy a KIA?

 

[Meccanoble]

Cold air intake is like $80 on eBay. Over the coarse of a year it will pay for itself. That's like spending a dime and getting a dollar.

Car already comes with a CAI setup. I dont see much improvement from aftermarket. Through my research, replacing the tube helps with sound and flow and possibly a very few ponies but still doesnt justify the price for MPG. For sound or something else, maybe...

I'm working on changing fluids to synthetic, maintaining a clean air filter, good tire pressure, the right tires, monitoring how you brake and how you accelerate. Anything passed this requires a different type of car IMO.

 

[ISU-152]

Whenever the GF is driving I'm always yelling "why are you accelerating to a red light"? Like we're in a hurry to stop lol

 

[pcowner]

Thank you for the replies, I also don't believe in spending a lot to get 1 mpg, I live in a city, but people drive like crazy here, Kia would be "crushed".

What kind of synthetics, Amzoil or Mobil sufficient? Also, I've read Bosch spark plugs are better then Autolite?

ubervic, wow 15 mpg not bad. it is 4x4 and I do drive in 2wd. I even cleaned the Air Flow Censor.

 

[pilot62000]

See my experience w Airaid Jr Intake:

http://www.tahoeyukonforum.com/thre...ors-airaid-jr-intake-tube.74498/#post-1017605

 

[dougo]

I have had this happen on two trucks were the knock sensors fails with no indication other the crappy gas milage on my 06 no codes were found, I found the issue because it reported a knock sensor wire short,Its Well known issue what happens is water gets under the intake and get in to the connection, The sensor is self my guess has been bad for the last 30k i had tried every thing with no improvment, After replacing the sensors gas milage returned, Just a thought
Gas milage was effected on both trucks 2-3 mile per gallon

 

[Jason_S]

Thank you for the replies, I also don't believe in spending a lot to get 1 mpg, I live in a city, but people drive like crazy here, Kia would be "crushed".

What kind of synthetics, Amzoil or Mobil sufficient? Also, I've read Bosch spark plugs are better then Autolite?

ubervic, wow 15 mpg not bad. it is 4x4 and I do drive in 2wd. I even cleaned the Air Flow Censor.

While saying KIA specifically was a bit "tongue in cheek", I've driven a Mini Cooper in DC, Houston and LA traffic and, both the car and I, lived to tell about it, so I do not accept that a "lesser" vehicle would be "crushed". If the way that you drive would result in a smaller car getting crushed, perhaps you should revisit your driving style and pick up a few MPGs for free.

While I will not dispute that some people have had an issue with knock sensors, the sheer number LS series engines in circulation would mean that, at the very least, a tech bulletin would exist if there was even the possibility of a widespread issue with a knock sensor.

Get/stay up to date on your maintenance, check your tire pressures, and check your right foot. If you want to go deeper, look at your tire style. An "economy" tune may help. Depending on who tunes it, a failed or failing sensor may be found during tuning.

If you want to go deeper still, look at your gearing. 3.54 (iirc) and 3.73 are the most common ratios. PPV's have 3.08 and I believe that SSV's had it also. Depending on your tire size, 3.73 to 3.54 will give you less "punch" starting off, but will give you better highway mileage. 3.08, even more so. If you just want around town mileage and could care less about highway mileage, going the other way might help, but that is a guess. However, cost and time investment will negate almost any savings.

Asking about oil brand isn't much different that asking which brand of beer is best. Name brand synthetics in the appropriate viscosity for your operating conditions will be comparable, but whether they actually improve mileage is debatable.

Also keep in mind that fuel with 10% ethanol versus fuel with out ethanol, will also make a noticeable difference in your fuel mileage.

 

[TheAutumnWind]

This has more or less been said in this thread, but this question comes up all the time.

Maintenance and driving style is key.

Sure you could get nnbs hybrid wheels (lightweight), a tune, longtubes and exhaust, and get a few more mpg, but how many miles will it take to break even?

 

[rdstrattan]

Get a 2-mode hybrid, except GM discontinued them after about 4 or 5 years of production. I have a 2008 Tahoe Hybrid I bought in 2011 when it came off lease. I get 20-21 mpg in city, as well as highway if I keep it under 70 mph. Also tow either my '30 Chevy sedan or '46 Chevy pickup (open flatbed trailer) and get about 13 mpg if I keep it under 65 mpg.

 

[CrashTestDummy]

Tire pressures and verify the front end is properly-aligned. Those will make notable differences in mileage. Making sure the MAF and TB are clean help, too.

 

[YukonandtheHOE]

Get a wideband o2 With a gauge then watch your Lambda as you drive, you can find the sweet spot and know when your the most efficient. but 9 times outta 10 gen4's are running crazy lean anyway..

 

[pcowner]

Mileage did improve (a bit to moderate) with inflating tires, I was a bit shocked that the tires were under-inflated. My were 20psi and the door tags say 30 psi.

One other thing I'd noticed while reading the manual. The traction control, it seems to be tied to engine and braking. I disabled on a trip and noticed significantly less drag by the engine and so did the instant mpg went up. Has anyone tried this?
Now the owner's manual suggests not to as driving with traction off can damage some components. Is this true? Also, it the traction tied to the stability control as I care much about having the stability control on and not so much about the traction control. When I disabled the traction control only 1 display light was lit.

 

[pcowner]

what is "MAF and TB are clean" ?

 

[pcowner]

"Also keep in mind that fuel with 10% ethanol versus fuel with out ethanol, will also make a noticeable difference in your fuel mileage."

All gas here in Oregon is 10% ethanol, where to find w/o it?

 

[quest51210]

I got a low mileage Passat TDI that gets 40mpg city for the price VW is giving me for it...

On another note, outside of knock sensors/harness I'd suggest intake gaskets while you are there. I'd also look into ordering some Kreen to clean out the engine and cylinders

 

[Tonyrodz]

what is "MAF and TB are clean" ?

Maf-Mass Air Flow
tb-Throttle Body

 

[quest51210]

I updated my findings of using Gumout Regane HM. Ran 10oz into a 1/4 filled tank, then two days later filled tank and dropped another 5oz in tank. So far I went from a high of 11.5MPG to 13.8MPG on two tanks since then. My Yuk is also more responsive and not jerky from start which I initially believed to be trans related.

As I said, my next endeavor will be running Kreen through an entire OCI