Tips on improving Fuel economy - 3.0i E53

[scirocco]

Although an old hand at Mercedes W126's, I am new to the BMW world. Just bought a 2001 E53 with a 6 Cylinder engine (3.0i).

I was wondering if members can provide me tips / mods / maintenance that can be done to improve the fuel economy.

Items like Tire Pressure, Air Filter, Spark Plugs would of course be in this list. Somebody told me that replacing the fuel filter also works but I find that difficult to believe. Can I do some mods / updates to the ECU? I do have the INPA Ediabas OBD software and cable.

[upallnight]

Trade it in for a X3. Almost the same engine but a LITTLE LESS WEIGHT.

[g300d]

Trade it in for a 330i, same engine but a LOT LESS WEIGHT.

Just kidding!

Check that the electric thermostat is working properly by monitoring average coolant operating temp via your gauge cluster display, test 7.

BMW designs these engines to run hot to improve fuel economy, you should see operating temps averaging low to mid 90's.

Thermostats that stick open cause the engine to run too cool and lower economy.

[tmv]

Pre-cat O2 sensors. They determine the A/F mixture ratio.
Fuel filter too. A clogged one will decrease engine performance -> less efficient -> decrease fuel economy.

[TiAgX5]

Fresh fluid in the TC and diffs, and align to minimum toe.

[Joshdub]

How crazy do you want to get? Light weight wheels with more economical tires should help.

[motordavid]

The 3.0 gets what it gets...auto or manual.
The usual: avoid heavy traffic, 5 min stop lights, (ain't gonna happen in Tampa, lol!), drive with light foot, and on and on.

None of the usual fixes are cost effective in terms of really increasing mpg in everyday driving, imo. One might get a quarter to a half gallon diff, over several tanks.

At current gas prices, one can skip Starbucks for week and be ahead, money wise, vs a laundry list of 'mods for mpg'.
GL, mD

[Ricky Bobby]

How bad is your mileage? I consider a 5MT equipped, I6, 3 ton SAV with 20" staggered wheels that gets 18.5 mpg mixed (which mine does), damn respectable mileage per gallon on 93 octane.

If I dropped down to lightweight 17" wheels/tires, removed some extra weight from the spare etc, maybe I'd be up 1 mpg.

I'd use the mileage ratings from BMW as a benchmark but wouldn't be worrying unless you're getting consistent under 15 mpg.

[StephenVA]

Every post is right on target on this fuel economy question. The X5 is shaped like a brick, the parasitic drain from the drive train is a killer, and we have tires sizes designed for HI Performance. All three of these are not easy work a rounds. Forget about the V8 models as that would take another email string.

Your right foot is more of a factor than anything else (unless the tires are at 50% recommended pressure). Tune up, clean injectors (no dripping, carbon on the back of the valves, etc), fresh filters, fresh oil using the right weights, good drive train fluid flushes, and a good quality fuel.

Alternative transportation: I have one of these in the garage for post office runs early Sunday mornings, other wise around here you get run over later in the day as traffic does not like little bugs in the road.....

[lhordmclain]

- Keep the truck well maintained (engine air filter, spark plugs, tire pressure, gas cap and more)
- Avoid excessive idling and stop/go
- Cruise control on a Highway with no traffic is your best bet
- Use high quality gas and manufacturer recommended octane rating

#1 avoid driving the X walk / ride a bike for a healthier lifestyle, public transportation or car pooling or city scooter or big bikes or all electric vehicle