Realistic max MPG for a 1390cc Volkswagen Polo

[svejoh]

Originally Posted by Bataleon

Hi,

I drive a 2006 model 1390cc 4-cylinder Volkswagen Polo. Currently I get around 38 US MPG (6.2l per 100 km) on the open highway when following the hypermiling tips listed on EcoModder.

Realistically, what can I increase this figure to, without modifying the car in any way?

Just as a comparison point, I get 6.2l per 100 km in my 75 hp WV Golf Mk3 1.6 when I'm just driving slightly too fast and not caring about the fuel consumption.

With some reasonable eco driving techniques (but still using studded tires), I got 5.1 l/100 km (46 MPG). I'm looking forward to see the numbers when I switch to my summer wheels and can remove the two extra driving lights I'm using now ...

[AndrzejM]

Hi,

I'm the owner of Polo 1.4 ('99). It's 60HP 8v engine and i can tell a lot about it's fuel efficiency.
During my many trips I was able to get as low as 3.83 l/100km (61.41 mpg US) with just target driving and some EOC on a long slopes down and killing the engine at longer stops.

Recently I've started P&G with EOC and the numbers went a bit lower ~3.5l/100km (higher in terms of mpg units - 67.2mpg US)

And I have crappy tyres, but since they are pretty new (my father bought them, when he was driving my Polo), so I won't change them soon I think.

I've slightly modded aero of my Polo - you can see all the changes here: My Polo modding thread

I would suggest to check your brakes - I suppose there is an unecessary drag, that is stoping your car and killing FE. My Polo is a bit lighter I suppose, but I haven't removed a thing from it to improve weight for now. But newer cars had a bit better aero.

Anyway if you want to discuss your Polo and mods, things to check or anything just drop me a line.

Good luck!

[Bataleon]

Thanks AndrzejM, very useful info.

Those are some impressive figures! The best I've managed over a 400km (250 mile) trip is 6l/100km (39 US mpg) and that is driving very carefully: an average speed of 100km/h (60mph), coasting in neutral down every hill, and tyres pumped to 40 PSI.

My Polo has a 1.4l 83HP 16V engine, so very similar to yours in terms of power output.

I'll take a look at your aero-modding thread, thanks. How much did the mods improve efficiency?

It could be brake drag so I'll check those too, along with the air conditioner belt which also adds unnecessary drag on the engine.

Cheers

[AndrzejM]

My Polo is very basic model. It doesn't have A/C, power steering. So the one and only belt driven thing under the hood is alternator.

Haven't measured how exactly my ods affected FE. I rely on my intuition and tank to tank numbers mostly. I have MPGuino installed as well so I can tell from the display everything... Even how strong the wind is It comes with the time...

But check your brakes, that's for sure. It's pretty easy. Just lift the car up with a jack and spin the wheel. it should make few revs before it stops with a decent push from a hand.

[Bataleon]

I'm very tempted to disconnect the A/C and just leave the alternator and power steering. I have a feeling the A/C adds a lot of drag, even when turned off.

MPGunio seems great. Did you build it yourself? I'm using Torque app at the moment which works well.

What distance are your trips usually? Most of mine are 4km (2.5 miles) each way to campus, resulting in an even worse average fuel economy of 8.5l/100km (I've been measuring since January). Also, what octane fuel do you use? I fill with 95 all the time, as recommenced in the Polo handbook.

I'll check the brakes this weekend. Thanks for the tip.

[AndrzejM]

In Berta, my previous car I've deleted A/C, power steering and mechanical radiator fan.

MPguino - yest I've build it myself - the one I'm using now is 5th in a row if I recall correctly. For me it's a best mod ever. It gives you a lot of feedback from the car. I've tested Torque app, but didn't liked it.

Distances are different from tank to tank. Sometimes my usual distance is below 5km sometimes it's one trip per tank. But with P&G with EOC I was able recently got average FE of 4,47 on the last tank, which I've used on a very short commutes. Soon I'm hoping for a long trip to Prague and back, so I'll see what numbers I'll get. I'm hoping for a new record! ;-)

[Bataleon]

What efficiency improvement did Berta gain after removing the A/C, power steering and radiator fan?

I'm keen to try and build an MPGuino. Did you follow these instructions?

4.47l per 100km is really good for short trips. I don't understand why my Polo efficiency is so bad. I'll be interested to hear the numbers from your Prague trip!

[AndrzejM]

Yes I've followed MPGuino's wiki mostly and t_vago's thread for the firmware. With some minor changes that was suitable for my setup.

Don't know what was the real difference before and after the changes I've made, because most of these changes were made during the engine restoration, so lots of factors has changed during the process. Sorry...

[Bataleon]

No problem. I'll check out t_vago's thread, thanks. Do you service your own Polo? Would it be possible for me to remove the A/C from the engine belt, or is it a big task?

[AndrzejM]

Yes I service all my cars myself. It's easy to remove the belt. If there's a single belt for A/C you just need to remove it. If the belt runs alternator and A/C you have to remove one and install a new one shorter for alternator only.

If you have any trouble take some pics and i'll tell you exactly what to do.