Air Flow meter

[Ric]

Wanted to confirm diagnosis, and purchase if diagnosis confirmed.

In Brissy best.

Air Flow Meter for MY07 GTB Lib.

Edit by Ric. Topic copied here for technical discussion

[bigBADbenny]

Wassup with yours?
I had mine cleaned by STi Docklands last service and checked it before the tune - all good very clean.
I made photos if you need to compare...

[Jaz]

Maybe nothing. It was cleaned from a fine dust film late last week, but problem persists.

It would appear the HKS foam filter catches small rocks and leaves and let's everything else through.

Dust = static = ?stufffed AFM.

[bigBADbenny]

My car ran better after the MAF was cleaned, but Matt's tune just transformed drivability.
I intend to just get the MAF cleaned every service and DIY clean both it and the HKS filter in between.
You can see some fine dust in the MAF pics but the (stock) alternative, if any, is an oiled filter which could be (alot) worse for the MAF.
The MAF is very delicate so I'm getting expert advice before I attack it!
I Iike the MAF velocity stack in the Cobb intake.
Would be awesome to incorporate that with the factory intake if possible.

ssssssssSSSSSSSSSSSSSSSUCK ch-chunter-ter PTSCHsssssshhhhheeeeeeeee
The Cobb is also wonderfully NOISY

[senator]

I been running the HKS hybrid for the last 95k and haven’t had any issues with a dirty AFM….. I’ve even got a modified air box which has air being rammed into it from the fog light surrounds.

Do you do a lot of driving in dusty conditions and is your air box correctly sealed???

[bigBADbenny]

Quoted from this thread:

"I cut up some neoprene to make a flat O ring type seal all the way around the 2 x halves of the plastic air filter holder/cage - for better sealing of the filter in the airbox.

Got my filter S/H so I'm not sure if they come with something similar standard."

but problem persists.

Symptoms?

[Jaz]

I been running the HKS hybrid for the last 95k and haven’t had any issues with a dirty AFM….. I’ve even got a modified air box which has air being rammed into it from the fog light surrounds.

Do you do a lot of driving in dusty conditions and is your air box correctly sealed???

I've done a couple of race days on dirty circuits, which has likely contributed greatly.

Air box has had resonator removed, but otherwise good seal. I'm going to Hit up Ric to move the discussion to technical to continue the discussion, which I'm pleased for.

[Jaz]

Symptoms:

-intermittent lumpy idle
-choking or, jerky acceleration, like it's dropping a cylinder, or pulling loads of timing.
-seems to happen during transition onto boost, and with increased load in higher gears, eg hills.

I had it at a mechanic late last week who did a full service and clean of the AFM. He did a drive on test while watching afm voltage on select monitor and reported voltage fluctuated, but couldn't watch long enough for speed of transition or flatline for instance.
New fuel filter and fuel pump fitted in attempt to rule out secondary issues, symptoms reduced initially, but now persistent.

Car is 07 GTB
3" TCP exhaust
HKS panel filter
resonator removal
Flash tune @ 14psi. - highest I've ever seen on my boost gauge is 1.07 bar so less than 16psi.


Advice I was given was that it was pinging, the ecu is pulling bulk timing, thus the massive hesitation, and that I should reload the standard map, see if the IAM improves and if not jump on a dyno to test afm voltage output over a range to make sure it's doing what it should, that and test fuel pressure over the rev range to make sure that's ok.

[norbs]

Order one from japanparts now. You might as well rule it out. Last thing you want is an dodgy afm to frag your motor

[bigBADbenny]

Since its 5 minutes to swap out, I'd locate a local member with the same car and do a temporary swap - for the differential comparo.
Advantage is that you'll know for sure you're testing a working MAF.
Sound like similar driving symptoms to my car prior to the tune, I'm getting full boost so perhaps even more unpredictable hesitation!

[norbs]

^^^ good post! !!

[PinkK]

Symptoms:

-intermittent lumpy idle
-choking or, jerky acceleration, like it's dropping a cylinder, or pulling loads of timing.
-seems to happen during transition onto boost, and with increased load in higher gears, eg hills.

I had it at a mechanic late last week who did a full service and clean of the AFM. He did a drive on test while watching afm voltage on select monitor and reported voltage fluctuated, but couldn't watch long enough for speed of transition or flatline for instance.
New fuel filter and fuel pump fitted in attempt to rule out secondary issues, symptoms reduced initially, but now persistent.

Car is 07 GTB
3" TCP exhaust
HKS panel filter
resonator removal
Flash tune @ 14psi. - highest I've ever seen on my boost gauge is 1.07 bar so less than 16psi.


Advice I was given was that it was pinging, the ecu is pulling bulk timing, thus the massive hesitation, and that I should reload the standard map, see if the IAM improves and if not jump on a dyno to test afm voltage output over a range to make sure it's doing what it should, that and test fuel pressure over the rev range to make sure that's ok.

Sounds like how mine was behaving before my tune. Who did your tune? Is the advise above given by the tuner?

[bigBADbenny]

+1 : I'd be making a bee-line for any reputable tuner, e.g. Matt KiDo/Throttlehappy in northern NSW. (pending MAF comparo or not)

[Boostaddict]

Has these issues only just started?? Or has it been like this since the last flash/tune??

It sounds very tune related to me ( and i know... not alot!! ). Get a Air Flow Meter onto it and check that its not running rich/lean.

[Jaz]

Tune has been in situ for 2 years. Symtoms present for 3 weeks.

I will however re load the standard tune as well to see what difference it makes.