Optimum Fuel Consumption...what should I do to achieve it?

[ravelcop]

guys, i have this Nissan Vanette for quite some time already and eversince, i had not achieved its optimum fuel consumption that others were claiming. right now, im suffering from her 4km/L consumption while others are claiming na 5-7km/L yung city drive nila

im pretty sure that i have been practicing fuel-efficient driving techniques and so far i have the following services done already:

1. Tune-up
- change contact points, spark plugs, fuel filter, air filter and adjust timing
2. Change oil
- i used the multigrade oil 20W-50 which is the one recommended by the manufacturer
3. Wheel-alignment
4. Correct tire pressure

guys, please advice me what to do next. i was thinking of having my carburetor overhauled but im not sure if it would improve something. so far, ok naman ang usok na binubuga nya, hindi maitim. or maybe clean my fuel tank. what else can you suggest guys? (aside from replacing my vehicle)

[1D4LV]

as much as possible, stay within 80 kph, at 2k rpm. yun ang pinaka efficient na takbo.
yup, and why not clean your carb? although wala naman syang matinding effect, medyo gaganda ang takbo ng sasakyan mo.
close your windows, while driving down the highways. it will lessen your drag (i think it was discussed here before)
avoid carrying heavy loads, if you can help it.

[ravelcop]

thanks for the reply gilmore.

although i have been practicing those fuel-efficient driving techniques like those you've just mentioned, what i'm suspecting is my vehicle. there's must be something wrong with it. AFAIK, im doing well in driving. maybe i should take your advice, overhaul the carb, or adjust its A/F mixture and make it run with more air and less fuel

[leinahtan]

There are great many factors which affect fuel economy, including vehicle size, shape, drag, rolling resistance, engine efficiency, engine size, gasoline composition, driving patterns, driving style, and even the time of year. Your Nissan Vanette's shape could be one of few factors affecting your FC.

[111prez]

mag khaos, hehehehe

joke only bro

but seryosli, tama yung mga payo above. is not just driving habits

its also tire pressure, vehicle load, accessories that add to vehicle weight (bullbars, rear bumper bars, etc) and even wheel alignment

[ravelcop]

thanks leinahtan, pero how come other vanette owners achieve 6-7km/L in city drive?

[niky]

The Vanette is a notorious gas guzzler, just ask any previous owner. I think we were only able to get between 4-6 km/l from ours in city traffic.

One major player in this drama would be your aircon. The Vanette's airconditioning is powerful, but the compressor places a heavy load on the engine. One counter to this is to darken your tints as far as possible without making it difficult to drive at night. Then buy window shades for your passenger cabin. I personally hate window shades, but you need to conserve fuel, right? Then find the optimum setting for your aircon, as low as possible while still being comfortable.

Clean your carb, it makes a huge difference. Also, as regards to driving technique, AFAIK, it's different for carburated vehicles, you don't necessarily engine brake while coasting, as carb vehicles use fuel when you do this (as opposed to EFI, which don't).

EDIT: the consumption is heavily dependent on your route and traffic. As the Vanette will guzzle while standing still (thanks to the AC), then driving a different route or at a different time might save you a lot.

Also, what year of Vanette is it? If it's the earlier one, then you can also install an auxilliary fan (the last edition, the Grand Saloon, had this already). It won't save gas, but it'll protect your engine from overheating. Mild overheating in traffic can also make your engine less efficient.