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Hi everyone. Have been talking to a guy at the gym re the Nissan Skyline Mass Air Flow sensor on our cars after we have found that he is getting about 700km's around town whereas i am getting about 520km's around town. Same vehicle (2008 350GT S), roughly same area times of driving and similar driving styles. i've have noticed that my car is idling quite roughly and he mentioned the Mass Flow Air sensor may be stuffed and this could be causing both the economy difference and the idling problems (as per this listing on TradeMe. http://www.trademe.co.nz/Browse/Listing.aspx?id=937190669)

Wondering if anyone out there can let me know if this could be an issue (have taken the AFM's out and they 'appear' to be ok - my car has just clicked over 50000km's) and worth me replacing them. I can see that there are plenty of other places online overseas selling these a whole lot cheaper than this guy.

Cheers for any advise guys.

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Have you tried cleaning them?

Realistically the o2 sensors should re-tune any discrepancies out of the map anyway. Could just be different driving styles?

There are many aftermarket AFM's out there, but in your case I would be buying genuine if possible. Unlikely both are faulty, if you got it on a Consult3 you would easily see if they are reading the same as each other.

700km around town for a V36 seems a too good for city driving... I reckon there is a good bit of crusing mileage in that...

In my 3.7 on the 10km school run I get about 12.5 l/100km, but on a good 50km freeway run, easily getting 8-9l/100km..

check your actual economy (L/100km), and get him to do the same KM/Tank is a poor indicator of fuel economy.. way too many variables. How low he lets his fuel tank run may well be different to how low you do. I could technically get over 700km out of a tank on my V35 with urban driving, but I would need to run the tank lower than I am comfortable with. I usually get to about 600-650km before filling.

Cheers for the advise/info guys. So pretty much don't just buy new AFM sensors and replace them without getting the car checked (i imagine Cockram Nissan in Christchurch would be the only place to do this) is what i am hearing. I've been using an app to monitor economy the last few fills and its showing about 12.8-12.7ltrs/100km's which concurs exactly what you have said nickcorr.

  • 3 years later...

What for? Measure actual use in litres per 100 km and report what kind of driving you do -short city runs -city and bursts on a motorway - country cruising...

Also check your tyre pressures and if you have a few km on check or replace your plugs.

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