My Fuel Economy

[Spook's_Skyline]

ok, i have 200rwkw rb25 and it uses 45/50 litres of fuel per 300km/s regardless of how me and the wifey drive it (it gets booted a bit, but mostly driving in traffic)

before i get the tune checked out, i want to make sure theres nothing mechanical that could be causing the bad fuel economy (it was pretty bad before the powerfc install, 350ks per 50litres, so im not convinced its the tune entirely (it may be a part of the fault)

what mechanical can cause bad fuel economy?

the car currenlty has its charcoal cannister unhooked (im getting it rehooked up)

the car also had a new throttle body (forward facing plenum) i believe its an 80ml ford jobby

car also has a fmic and hks cam gears exhaust

i want to go see my mechanic and give him things to check that can be causing such bad economy

there is always a heavy fuel smell when reversing, and often i can see fumes coming out of the petrol tank cap

dont see excessive smoke out the back, no black marks on rear bumper

what else can i get my mechanic to check?

[SECURITY]

most common: o2 sensor, leak in the fuel tank, dodgy fuel pump (filter), clogged injectors

least common (but still possible): leak in the fuel lines, leak at the fuel filter, hoses might not be tight enough to hold the fuel pressure.

things like that.. i saw a thread about a leak in the fuel tank floating about a while ago, search and you should find it.

get your fuel pressure tested too.

[Spook's_Skyline]

whoops, forgot to mention, ive already replaced the o2 sensor with the NGK one for r33 (correct plug)

it works correctly

also have a walbro fuel pump

[SECURITY]

look into everything else then.

[R33S2]

have you cleaned the AFM, also check for vacuum leaks.

[Spook's_Skyline]

i havent cleaned my afm;

i will though, ta;

[predator]

manual or girl shifter?

[RANDY]

lol! I have no leaks, everything else checked, 02 replaced etc etc etc

Stock as a rock, and I get 350 to a tank EXACTLY, no matter how I drive.

[BSK]

have you cleaned the AFM, also check for vacuum leaks.

how do u clean an AFM?

[dangerous_daveo]

how do u clean an AFM?

Pull it off, get some electrical contact cleaner, spray away.

Spooks, I doubt the afm clean is going to get you the economy your after. Id recomend stop wasting money on things it might be. Get it down to Matty and get it on the dyno. He should be able to find the problem very quickly. Sure he is exxy, but if he can say this is what needs fixing, you dont need to do this and this, you have just saved money.

[khunjeng]

fuel filter been changed lately?? I chnaged mine on another cra recently and OMFG did it make a difference..

but if ur still having trouble...dyno and have a look at AFR etc...and see whots going down!!

KJ

[Spook's_Skyline]

im cleaning the afm this arvo, but i would have thought there would be performance issues if it was dirty, theres not, she goes good

yer, sounds like i mite just have to get it on the dyno

i need to do something, as ive just moved house and im gonna be filling the car up 3times every two weeks just running around, which is gonna send me broke

[R33S2]

Yeah I was covering another base in the system, doesnt hurt anyway.