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i got a r33 gtst with fmic, cat back exhaust and a pod filter

im lucky to get more than 250 on afull tank of vortex 98 driving slow!!!

ive changed the o2 sensor but that doesnt seem to have worked :S

also bought a new afm

any ideas???

I had a similar prob where my car was just sculling fuel, its cos of the standard computer. I got a fuel controller and had it tuned and it fixed the prob, now a full tank lasts me ages. It not only uses less fuel but i get more power aswell due to leaning out of the mixtures. Get an SAFC or PFC or similar this will fix your prob. :(

yeha the fuel adjuster seem the way i wnat to go, but 250 is wayyy to low :S im certain that my afm is good, and i changed the o2 sensor!

im worried if i tuen it and reduce the ratios the computer will do somehting stupid like run lean and ping!!!

but the car aint worth having if i get 230-260, thats trash! a pushrod v8 gets better than that! and vortex 98 is 98ron so it should be similar to bp ultimate and the car sems to run rich.

might be a stuffed cpu but its all good. im almost finished building a jaycar fuel adjustor and will install and dyno it soon. ill keep u guys upto date with what happens

yeha the fuel adjuster seem the way i wnat to go, but 250 is wayyy to low :S im certain that my afm is good, and i changed the o2 sensor!

im worried if i tuen it and reduce the ratios the computer will do somehting stupid like run lean and ping!!!

but the car aint worth having if i get 230-260, thats trash! a pushrod v8 gets better than that! and vortex 98 is 98ron so it should be similar to bp ultimate and the car sems to run rich.

might be a stuffed cpu but its all good. im almost finished building a jaycar fuel adjustor and will install and dyno it soon. ill keep u guys upto date with what happens

Vortex is 95 octane

i got a r33 gtst with fmic, cat back exhaust and a pod filter

im lucky to get more than 250 on afull tank of vortex 98 driving slow!!!

ive changed the o2 sensor but that doesnt seem to have worked :S

also bought a new afm

any ideas???

Try cleaning the hot wire in the inlet just down from your pod. The oil that you put on the pod[ K&N or my Unifilter] coats the hotwire and insulates it so the ecu thinks it needs to pour the fuel in.I use CO contact cleaner and gently use a cotton bud to do it.

It shouldnt be running so rich and using so much fuel. Just buying a fuel adjuster is masking the actual problem. Have you tried an ECU reset? You should also try an ECU diagnostic as one of your sensors may be playing up.

thats exactly what im thinking!! i dont wnat to amsk the problem cause itll come back to haunt me!

dude what is the hotwire ur talking about? cheers

It shouldnt be running so rich and using so much fuel. Just buying a fuel adjuster is masking the actual problem. Have you tried an ECU reset? You should also try an ECU diagnostic as one of your sensors may be playing up.

thats exactly what im thinking!! i dont wnat to amsk the problem cause itll come back to haunt me!

dude what is the hotwire ur talking about? cheers

Bazz. The hot wire tells the ecu how much air is flowing through the metering system.If you take the pod off [there is probably a mesh cover in there]and look down the induction tube you will see a brass spigot with a large slot cut in it. This brass spigot comes through the side of the tube and a six or seven pin plug goes off into the wiring loom. The way hotwires work is there is a current ,known to the ecu through the small resistance wire. As more air flows over the hotwire it cools therefore to keep the known resistance more power is sent to the hotwire.This is how your ecu knows how much air is flowing through the motor, so therefore the ecu changes the fuelling[pulsewidth and duration] to suit. The lambda sensor does a similar job in the exhaust.

ohhhhhhhhhhhhhh the hotwire in the afm!!!!! yeha dude i did that already. i did a once oiver on the o2 sensor wire anmd some of it looked like it was in bad nic, so i changed it and wala!!! did 100km on first qurater :)

so basically guys if ur running rich this is what worked for me

1)reset the cpu

2) change o2 sensor (or if its fairly new clean it with contact cleaner ~$7 at dicksmith) and reset again

2) make sure all the elads to the o2 sensor are healthy!

3) clean the AFM with contact cleaner and reset again

4) use bp ultimate :O

this worked for me. my next step would have been to put the car on the dyno to see that the other sensors are healthy and that the cpu maps are good!

anyways thanx for all the help

cheers

Edited by bazz

i got the o2 sensor from repco. the direct fit (with the EF plug) cost me $82. i used a pipe socket to remove it, or you could do it with a spanner (21 or 22 cant remeber exactly). i did it myself (and i know nothing about cars). the brand they gave me was ACA. it had a blue wire and 2 black. using clip connectors i put the blue to the big brown wire on the car (r33 93model) and the other 2 are just heat so doesnt matter. then u reset ur cpu and its all good

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