R34 Gtt - Chewing Up Petrol

[GH05T]

is your ECU throwing any codes?

[SoulScene]

I get on average 260Kms a tank with my GTT aswell. Engine wise it's completely stock. I've cleaned AFM changed the fuel filter, fuel filter was completely clogged I noticed a slight difference in fuel consumption, maybe I'll have to go for the O2 sensor and new plugs see if that helps as well

[GH05T]

jesus how are you all putting up with these figures!

[Cassbo]

Also if someone has put a low temp thermostat in, or yours is stuck open, then that will also add to poor fuel efficiency. Cold crank enrichment tapers off at 70C so the quicker she gets up to temp the better.

This. I put a Nismo thermostat in my Riceline, water temp now sits at 60C unless I'm at a track day. I struggle to get 12L/100kms, when I first bought the car I easily got 9.5L/100kms on the highway

[Charles89]

So OEM/stock thermostat is best for fuel economy? What about oil cooler with built-in thermostat?

[MrRx7s3]

Yeah the exhaust leak is on the turbo to dump pipe gasket, I changed the 02 sensor about 15000kms ago with a brand new genuine one from Nissan.

[blind_elk]

I do do alot of short trips, I'm running PFR8 plugs with a 0.9 gapp,

Short trips, incorrect heat range plugs - no wonder you have absolute crap economy.

Try running a 6 heat range for starters. And plan your trips better so the engine operates at the correct temperature for most of the time.

[MrRx7s3]

What plugs do you recommend.

[Charles89]

NGK BCPR6ES or BCPR6E will be fine

[Chris32]

So OEM/stock thermostat is best for fuel economy? What about oil cooler with built-in thermostat?

Mines got a oil cooler with no thermostat, oil temp sits between 70-80 degrees. I run BCPR6ES plugs with the standard gap, which is 0.8mm from memory.

I've found V Power to give me greater mileage than BP Ultimate for some reason too

[MrRx7s3]

I ran those before the PFR8S and it was the same thing, well the owner in Japan did fit quite a few Nismo parts to the car, I'll check what thermostat is in there and give the AAC valve a clean aswell, is there a way I can get error codes through a power fc by any chance, thanks.

And whats the difference between the BCPR6ES and the BCPR6E? And could some refresh my mind the lower the number the higher the plug temp correct? thanks.

Edited November 12, 2013 by MrRx7s3

[Ben C34]

Yep lower number is hotter. Has anyone checked their timing? That would have an impact on economy. Also should be talking litres per 100 ks as too many variables with a 'tank' of fuel.

[GH05T]

true but seriosuly when were talking a difference of 550km- 250km, i dont think brimmed vs filled is going to mean too much.

[MrRx7s3]

Do you think that I might have an injector leak could that be possible.

[Ben C34]

true but seriosuly when were talking a difference of 550km- 250km, i dont think brimmed vs filled is going to mean too much.

Its not the difference of how full, but how empty it is when you fill it. Accuracy of fuel gauge and how far you are willing to with the gauge below the E.

[Ben C34]

Do you think that I might have an injector leak could that be possible.

Yes you could have a leaky injector. So could anyone.

[R.3.2.G.T.R]

mine been tuned a while back after i re-did my fuel pump mod for battery voltage, crap economy, around 300km on full (72L tank IIRC), o2 sensors turned off, bcpr6es plugs, no leaky injectors, although i do short trips (10km) each way to work, low temp sender perhaps buggered?

[niZmO_Man]

Crapped out AFM makes a difference, solder fix those fkers!

[Dose Pipe Sutututu]

mine been tuned a while back after i re-did my fuel pump mod for battery voltage, crap economy, around 300km on full (72L tank IIRC), o2 sensors turned off, bcpr6es plugs, no leaky injectors, although i do short trips (10km) each way to work, low temp sender perhaps buggered?

Install a wideband o2 and see what your car is doing. I've seen lazy tuners who don't even care too much about off boost injection maps and just rely purely on o2 closed loop to work out the mixtures.

[viper2002]

I find mine is chewing up a fair bit of petrol as well. I've put some fuel injector cleaner in which should help, also going to replace the spark plugs and clean the AFM sensor to see if that makes a difference.