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AFM readings after CAI install:

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Fitted a cold air duct up the left hand guard to the HKS Pods, on the GTR. Noticed straight away Air Flow Reading on the Power FC Hand Controller jumped quite abit, & is close to maxing out hitting around 4800.

Also noticed...

1. some occassional jolting when accelleratoring.

2. the smell fuel

3. And more backfiring

4. Using more fuel "After the power FC" I'm getting 260-280k per tank" 60% hwy

Power FC O2 Sensor Q:

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Whats the go with >ETC >Functions - directory What does this do? I'm asking because I was playing around with & changed a few of the settings from yes to no & visa versa. I didn't touch the Boost Controller, but did change the O2 Sensor. I also noticed 2 drectories for O2 one is FB the other is below. Have I stuffed anything up?

Tuners In Victoria

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I'm planning on going to ICE & have them retune the Power FC, but someone mentioned to me a Guy call Vince from Promech in Richmond who was part of Gibson motorsport & is apprantley factory trained? Any comments or opinions?

Yep, I too seem to be getting similar problems with my new CAI setup too but its only for the first 4 minutes or so when the engine is cold (see post http://www.skylinesaustralia.com/forums/sh...ead.php?t=30533 ). However, my airflow seems to be fairly consitant:

AFM Voltage:

1.05 volts when idleing

2.00 volts or so when cruising

3.00 volts when accelataring pretty hard

3.5-4.00 when kicking it in the guts

I think the flow of the air should still be the same but because the air is colder initially (more dense) its getting too much oxygen. Though I'm not sure if the engine is overcompensating by adding more fuel???

I did wind back the timing a bit too (was detonating with crap fuel & nismo tuned ecu) so that could be affecting things too.

But I can definitely concur with:

Frequent jolting when accelatring

rough ride

& possibly more fuel consumption.

For the first 3-4 minutes but then it seems to fix itself.

For this period I am shortchangeing because when the revs get high its really shuddery. Also when the boost winds up I dont get the power I usually get either & sometimes the boost guage vibrates +/- on 0 bar (but I think this is due to the power shuddering). Again, only for the first 4 minutes.

Anyway, when I get a new timing belt I'll install some cam gears & wind the timing backup & see how things go.

With the powerfc I'd have thought it would be pretty easy to monitor AFR & injector duty.

Anyway, sorry for hijacking the thread but it seems like a similar problem.

Cheers,

Penfold

meshmesh, O2 sensor is used for idle and cruise - it will lean out the mixtures and improve fuel economy - so best on if the car doenst mind, sometimes they seem to run better with it switched off, maybe due to faulty O2 sensor????

If the problems you hare having is with cold start, you can adjust the enrichment at the water temp function in the settings menu. The first setting is enrichment at idle, the second is idle under load (such as turn steering wheel). Check your water temp, then try knocking the enrichment back until the idle changes. Just make sure you note the starting point so you can return to it if its worse.

If the afm voltage has risen, but the load (rpm) point hasnt changed (maybe as suggested due to denser air) it will mean the power fc is reading from a different part of the map. This may explain running rich on the road, and poor driving. Its only a guess, but it doesnt quite make sense to me, as it would mean your car would run like a dog when it gets colder - which usually the opposite is true.

I think as you mentioned in the first post, best is to get it on a dyno so you can see what is happening properly:)

Sorry, this post isnt much help, rambling on a bit:)

Yeh, with regard to my problems (penfold) its definitely only for the first 3-4 minutes if the car has been left for several hours (+6 hours) - other than that it runs really really well. But I haven't installed my PFC yet - just a nismo tuned ECU but like I said I did retard the timing a little but I'm a bit of a newb & was unsure of how this (CAI & backed off timing) would effect things so greatly for that first 3 minutes of drivsing (but idleing is fine). Sorry again for stealing the attention but I though the two seemed related & was looking for answers.

Yeh, with regard to my problems (penfold) its definitely only for the first 3-4 minutes if the car has been left for several hours (+6 hours) - other than that it runs really really well. But I haven't installed my PFC yet - just a nismo tuned ECU but like I said I did retard the timing a little but I'm a bit of a newb & was unsure of how this (CAI & backed off timing) would effect things so greatly for that first 3 minutes of drivsing (but idleing is fine). Sorry again for stealing the attention but I though the two seemed related & was looking for answers.

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