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hiway2002

Hi there, I've recently got a Nissan X-Trail 2006 2.0 petrol 4-speed auto. From a few rounds of trips I found the fuel consumption around 8.5KM/L local drive and 10.4KM/L highway. Is that normal or quite bad? Thanks.

Anon

The 2.0L petrol X-Trail isn't the lightest on fuel and your fuel economy readings seem realistic. However, a good service might help to slightly improve on the fuel economy.

hiway2002

Thanks Donavan for the prompt reply. I've just done service (using Penrite fully synthetic 5w-40) and new air-filter. My mechanic told me the spark plugs wouldn't need replaced until hitting 100K (mine done 83K). And what's the best tyre pressure for my car? It uses 215/60/R17 alloys. Thanks a lot.

Anon

33 PSI front and rear will be fine.

hiway2002

thanks again. I have read about tuning/programming ECU which could improve fuel efficiency or performance, do you think my car needs that? anything else could make improvement? would using #95 petrol do any good (balancing off the price offset)? Cheers.

hiway2002

Hi Donavan, would you be able to further assist in answering my last question? Thanks a lot.

Anon

You should see a slight improvement in fuel economy using the higher octane fuel but you pay a premium price for it and therefore you are unlikely to see any financial gains. I do not recommend engine ecu tuning (aftermarket re-mapping) as you risk causing reliability issues. The Nissan engineers know what they are doing and map the ecu to achieve both reliability and fuel economy.

Check the tyre pressures on a regular basis as under-inflated tyres will cause higher fuel usage. You should have a mechanic check the spark plug gaps and condition as worn spark plugs will cause higher fuel usage.

hiway2002

Thanks. So you suggest I take it to Nissan mechanic for ECU check? I found a thread on web instructing a reset in the following steps (after changing air-filter as the mix of air and petrol in engine would be different),

1. Start up your X-Trail and allow it to warm up to its normal idle.
2. Next turn off the engine.
3. Locate the fuse box located under the bonnet and next to the battery. Pull out the 3 fuses: ENG CONT1 (15A), ENG CONT2 (10A), ENG CONT3 (20A). Refer to the pics below. Keep the fuses out for at least 5 minutes. This will cut all power to the ECU.
4. Plug the fuses back in and close the bonnet.
5. Start your X-Trail making sure NOT TO TOUCH THE ACCELERATOR WHEN YOU START IT UP. This is very important.
6. Let the X-Trail idle at its normal idle speed for about 4 minutes, then turn off your engine.
7. Start your X-Trail again and you're done.

which seems very easy to follow and non-risk to just disconnect the power? any comments? many thanks.