mods that will improve fuel economy?

[Vigilante375]

Originally Posted by ken1137

Yep, 21 mpg isn't bad...I'm still laughing at the fact someone has a Zune

Originally Posted by ryancappuccino

Zune! ...I had one too back in the day....

Nothing at all wrong with a Zune. Works better than my wifes iPod/iTouch and has a better battery life too. If I want to get on the internet or play games, I'll use my S6.

Sorry I'm not on the Apple bandwagon when something else works better for cheaper and a lot easier.

I know this is a real old thread but to the comment about 55-60 being the best spot for MPG and its going down going higher in speed is wrong. I drive ~65 to work on the Interstate for about 25 miles a day with maybe 5 miles on roads going 15-45 MPH near my house and work. My MPG is usually around 25, thats just normal driving. No WOT pulls or whatever. Now, coming back from the airport and doing maybe 70-75 MPH my MPG gets close to 30. This is a stock 135i 6 spd. The numbers don't like when I do the calculations myself, miles divided by gals put into my car.

[B777flyboy]

Originally Posted by Allencic

For a 135 I suspect your mileage is pretty typical.

In a long lifetime of driving I've had a number of good friends who complained about how lousy their mileage was. Without exception they all had several driving traits in common. First, they used the accelerator and brake pedals as on/off switches. Either full on or full off. Frankly, to ride with them was really unpleasant and often simply unsafe. Second, they never looked far ahead at the traffic so they could make smooth transitions in speed. An obvious red light ahead was usually met with a sudden, surprised need to stop quickly instead of smoothly. Third, their lack of situational awareness of the traffic around them often found them jammed in packs of cars going either too slow or fast, on and off the brakes and gas. Simply unpleasant, uneconomical driving style. Their jerky driving style often resulted in moving violation tickets. In short, they were crappy drivers.

This is flat out the single best point. Only other possibility is if u have a manual and know how to manage energy. I get avg of 23, most of which is slower speed due to traffic. I have the 135 with a stick. I also consider myself a spirited driver and drive how I want to ( not economically) all the time. Little things add up a long way. My breaks for example are showing 70 and 80 k miles til replacement.

[BMW135pls]

Gas mileage is something that should be monitored, but not strived for. Use high quality 93 octane gas from a good station, like Sunoco, Shell, BP, avoid independents and no names, and avoid Costco. If you delete some of your catting, you can improve mileage. Up your tire pressure and you can improve mileage again. Adjust your alignment for 0 toe and camber front and rear and you'll get better mileage, but why would you want to?

21mpg is not bad at ALL. If you were getting 15mpg while driving "normally" I would agree with you, but you shouldn't make yourself uncomfortable trying to get a little better mileage. Trying to save a few bucks in mileage is a very poor way to go about saving money. Calculate your gas spending on a yearly basis, and I think you will find that you aren't spending as much on gas as you think you are. If you REALLY kill yourself trying to drive like a good boy and do all the right moves, then you may save something like $500 over the course of an entire year, again depending on how much driving you actually do. You'll have to ask yourself though, if you are going to such extreme lengths, did you buy the right car? A turbocharged rear wheel drive sportscar is not really something one typically buys to practice extreme self-control.

Enjoy the car for what it is. Beat on it, make some noise, burn some rubber and fuck the mileage. If that sort of thing doesn't appeal to you, or you just bought the car for looks and status, do yourself a favor and trade it in for one that's more your thing. No judgment intended, the car may just not be for you.

[Vigilante375]

Avoid Costco? I use it every so often and my MPGs are still the same. Both in my car, the wifes Camry and our Tundra. Maybe the Costco in your area just sucks.

I'll only avoid it when the gas station is like a freaking parking lot.

Other than that, I use BP, 76 (mainly), Shell and any other gas station. Shell seems to bring my mileage down a tad though.....

[BMW135pls]

Originally Posted by Vigilante375

Avoid Costco? I use it every so often and my MPGs are still the same. Both in my car, the wifes Camry and our Tundra. Maybe the Costco in your area just sucks.

No it's not a regional thing, it's a corporate level thing. I'm in the petroleum industry as a repair/maintenance technician for a variety of different banners. Costco has the lowest prices of anyone usually, and you get what you pay for is as applicable as it usually is. They buy the same cheapest you can find, bottom of the barrel gas as the no name and other cheapo places do. Whoever is making it the cheapest that day. That mentality is certainly not limited to Costco by a long shot.

[germ]

Your mileage is typical.

I wonder if the various modified chips that are available could have a map that reduces turbo pressure instead of increasing it. That would probably do more than all the other things that have been suggested (at the cost of reduced power, of course).

[Yeineken]

Originally Posted by Allencic

For a 135 I suspect your mileage is pretty typical.

In a long lifetime of driving I've had a number of good friends who complained about how lousy their mileage was. Without exception they all had several driving traits in common. First, they used the accelerator and brake pedals as on/off switches. Either full on or full off. Frankly, to ride with them was really unpleasant and often simply unsafe. Second, they never looked far ahead at the traffic so they could make smooth transitions in speed. An obvious red light ahead was usually met with a sudden, surprised need to stop quickly instead of smoothly. Third, their lack of situational awareness of the traffic around them often found them jammed in packs of cars going either too slow or fast, on and off the brakes and gas. Simply unpleasant, uneconomical driving style. Their jerky driving style often resulted in moving violation tickets. In short, they were crappy drivers.

+1

I do a highway trip of 150 miles twice a week and get 30-35 mpg. All in your driving habits.

My rules.

Red light ahead: Coast to it. Even if the dipshit behind you doesn't realize and rides your ass or goes around.

In traffic jam: Coast. Don't speed up and slam on your brakes. Just a waste of gas.

Heavy traffic: just keep two car length behind so your not constantly going from throttle to brakes. This allows you to just let off the throttle and coast until the group speeds up again.

[MightyMouseTech]

For good FE when not hooning about:

Coast, coast coast! This is a big one if you have a manual! The injectors are off if you are in gear and coasting. You actually need to accelerate fairly quickly from a light (rule of thumb is to get to highway speed at double your 0-60 time) get to your desired speed, and then stay at that speed without change. To get good FE, you need steady state cruising, no acceleration, and you won't get good FE until you are cruising steady in 5th or 6th.

Make sure tires are at proper pressure.

Running 5W30 instead of a 5W40 also makes a big difference, also make sure ALL the fluids are full synthetics.

Run the highest octane you can.

We can have our cake and eat it too.

My best tank was around 33 MPG, avg speed was around 95 km/hr for that tank.

[Solo_M_Tech]

With very careful throttle control on long Autobahn runs i have maxed out at 31 MPG, 26 average. however, if I drive anything close to normal, i average 22mpg. I've never been too worried since I knew the 135i wasn't an economical car. I just like to have fun at the expense of my wallet lol

[bmw1racer]

Originally Posted by ptack

No, it's a stupid rationalization to say you're smart with your money so you bought a 300 hp convertible. You made an emotional choice to buy a very unpractical vehicle which you are trying to make economical.

+1.

[ShocknAwe]

Not the point of the car. It would have been nice to have cylinder deactivation, but we don't.

[PA135i]

Originally Posted by B777flyboy

My breaks for example are showing 70 and 80 k miles til replacement.

Good luck, but that will never ever happen with OEM BMW brakes.
These brakes are good for 40K tops.

As far as the topic .. driving style is the single most limiting factor in gas mileage. I can see my mileage increase as the "school" traffic is pretty much gone now. Another option for increase is to get a tune. The tune optimizes for 93 octane which usually increases mileage by 1 - 3 MPG. Of course if you get on it with the tune then you will probably get worse MPG.

[five_timer]

I just had my eccentric shaft sensor replaced. Symptoms were stalling upon start, and crappy gas mileage. After the fix, I'm now back up to normal of 25 mpg, which was down by 3 to 4 mpg before the repair. Car has 60k on it.

[Xyloft]

when you say "mostly highway" is it cruising at 70 mph or stop and go at 10-30 mph.


Of course, drag increases the faster you go so there will be a a difference between 70 and 90.

is 22 mpg, your computer read out or actual? whats the average speed on the computer? i reset both MPG and AVG Speed every so often. the tanks where I have a 35-40 mph average speed i'll only have 25-26 mpg. if i have a 45-50 mph avg speed, i'll get 30 (in a 128).

[Wakka]

Best mod to improve the MPG would be sell the 135 and get a i3.