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Hey peeps,

After reading a bit about fuel consumption, I think my afm might need replacing - as I'm lucky to get 350 - 400kms from a tank and that's even when driving on freeways & in 5th gear. Does this sound right - would a new afm improve this?

I remember seeing someone on the forum selling brand new afm's for around $100 or $110. Does anyone know who that would have been - they seemed to have quite a few.

Thanks.....hope everyone had a great new years.

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I don't think it's your AFM that's making your car drink more petrol or that you're getting less millage.

You may need a tune which would involve your AFM but I don't think you need your AFM replaced per say. It could also be your engine, the way you drive or a few other things. For example, I tend to drive off boost more now and get much more millage from my car - obviously...however, a tune would be good...however, if you really want a new AFM, go for a Z32 (AFM from 300ZX's) as they're the best bolt on replacement but you'll need a tune for this.

Good luck.

AFM Can be cleaned, must be done when it is cold, I use CO Contact cleaner.

Check the Oxygen Sensor is functional, laptop with consult, multimetre, greddy informeter etc. a new one is ~$78 There are many threads on this.

When did you last change your plugs(and service the car?) I personally did it when I did my oxy sensor.

Also check tyre pres.

if your AFM is shagged the car will run like ass, lots of smoke, overfueling etc

if you are getting sub 350kms to a tank the AFM is fine

things to check

check and replace 02 sensors - they have a limited lifespan and only

they die after around 50,000kms ish and the part is about $100

the 02 sensor is solely responsible for getting good fuel economy. with a good setup you can have plently of power and 400km's to tank each time easily

if you were getting sub 300kms to a tank, then 02 sensor is toast

over 300kms to a tank is fine. stop loading the engine up and stop bringing it on boost, problem solved

if you dont believe me (or others who have said the same) give your car to your girlfriend or mum to drive for a week

i bet they get over 400kms to tank

also what do you classify as "to a tank" are you measuring the same way each time

do you run it empty? do you fill it up to the top? how many litres do you fit in when you "think" its empty

the gtst fuel gauge goes past E before you are empty and then the idiot light comes on

the difference between near E and past E is around 40kms (at least) of light cruise

the 02 sensor is usually the most common thing to be the cause of poor fuel economy

as most work shops / services wont ever check it etc and theres no idiot / warning light that comes on when its dead

so you wont know if the sensor is dead / lazy the car will just run like normal.

you can find a replacement 02 sensor to suit ECR33 from your local repco etc

the same sensor matches the ford falcon EL which is a generic 3 wire 02 sensor

be sure to note, you must cut the wires and fit it yourself, it doesnt come with a plug

I don't think it's your AFM that's making your car drink more petrol or that you're getting less millage.

You may need a tune which would involve your AFM but I don't think you need your AFM replaced per say. It could also be your engine, the way you drive or a few other things. For example, I tend to drive off boost more now and get much more millage from my car - obviously...however, a tune would be good...however, if you really want a new AFM, go for a Z32 (AFM from 300ZX's) as they're the best bolt on replacement but you'll need a tune for this.

Good luck.

What if he still has the factory ECU? How you going to 'tune' it?

if your AFM is shagged the car will run like ass, lots of smoke, overfueling etc

if you are getting sub 350kms to a tank the AFM is fine

things to check

check and replace 02 sensors - they have a limited lifespan and only

they die after around 50,000kms ish and the part is about $100

the 02 sensor is solely responsible for getting good fuel economy. with a good setup you can have plently of power and 400km's to tank each time easily

if you were getting sub 300kms to a tank, then 02 sensor is toast

over 300kms to a tank is fine. stop loading the engine up and stop bringing it on boost, problem solved

if you dont believe me (or others who have said the same) give your car to your girlfriend or mum to drive for a week

i bet they get over 400kms to tank

also what do you classify as "to a tank" are you measuring the same way each time

do you run it empty? do you fill it up to the top? how many litres do you fit in when you "think" its empty

the gtst fuel gauge goes past E before you are empty and then the idiot light comes on

the difference between near E and past E is around 40kms (at least) of light cruise

the 02 sensor is usually the most common thing to be the cause of poor fuel economy

as most work shops / services wont ever check it etc and theres no idiot / warning light that comes on when its dead

so you wont know if the sensor is dead / lazy the car will just run like normal.

you can find a replacement 02 sensor to suit ECR33 from your local repco etc

the same sensor matches the ford falcon EL which is a generic 3 wire 02 sensor

be sure to note, you must cut the wires and fit it yourself, it doesnt come with a plug

OZA 395-E2 from memory is the plug in one to suit GTST Confirm when you buy it. Trade price is approx. $78.

there you go - get that part # then

is that just for the loom and plug ? or plug, loom and sensor?

cos my sensor when i brought it was $140 from repco, generic 02 sensor 3 wire to suit el falcon

there you go - get that part # then

is that just for the loom and plug ? or plug, loom and sensor?

cos my sensor when i brought it was $140 from repco, generic 02 sensor 3 wire to suit el falcon

plug, loom, sensor. I paid $78 at bursons.

think i might get mine looked at also, my stagea is luck to see 380km out of 65ltrs i think.

How is it on the freeway?

... theres no idiot / warning light that comes on when its dead so you wont know if the sensor is dead / lazy the car will just run like normal.
Jaycar make a little kit that will show what is happening at the O2 sensor. About $35, DIY.

The R33 tank is 65L, the empty light comes on when there's about 10-15L left :)

How did I know? When I had my R33, I always fill it up full then drive until the light comes on, then refill. And whatever I put in minus the tank size = what was left in the tank. :)

Ahhh thanks everyone. I think the O2 sensor is what I was thinking of....somehow got it mixed up with the afm.

I generally drive it off boost and do a lot of freeway driving. It drinks that much that even if I'm in a 70kmh zone I'll generally drive in 5th gear. I'll generally only fill it once the petrol light comes on. I rarely drive the car because it just costs too much...so hopefully changing the sensor will help fix this. I'm planning on a pfc in the next few months, so with any luck that will also help and produce a bit more power.

I think it was the O2 sensor someone was selling on here for around $78 - maybe a bosch one....but who knows - I stuffed up by remembering it as an afm, so the guy could have been selling a packet of chips for $300 the way my memory is going.

Ahhh thanks everyone. I think the O2 sensor is what I was thinking of....somehow got it mixed up with the afm.

I generally drive it off boost and do a lot of freeway driving. It drinks that much that even if I'm in a 70kmh zone I'll generally drive in 5th gear. I'll generally only fill it once the petrol light comes on. I rarely drive the car because it just costs too much...so hopefully changing the sensor will help fix this. I'm planning on a pfc in the next few months, so with any luck that will also help and produce a bit more power.

I think it was the O2 sensor someone was selling on here for around $78 - maybe a bosch one....but who knows - I stuffed up by remembering it as an afm, so the guy could have been selling a packet of chips for $300 the way my memory is going.

Go to bursons and get a bosch one to suit R33 GTST OZA 395-E2 $78

You will need a special tool to change it, it is approx. $22 or you can borrow one if you know someone with one. If you still have a standard dump pipe and plan on changing it yourself in future, might be worth buying the tool. Make sure it matches your socket.

I found dump/front/highflow cat helped economy on my stagea.

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