Erratic idle and knocking sound

[glend]

Sort out your issues before you consider a GDE tune.
They are known to need engine mounts at some point, particularly the drivers side due to down pipe heat. It would likely rattle abit if the mount was bad. It's suppose to sound like marbles rattling, see if you can trace the sound.

[KJ75]

As I mentioned there is no issue when MAF is unplugged, idle and acceleration is fine.

When MAF is plugged in there is a pause of acceleration at around 900 rpm, then accelerates again. Idle is also very low and idle almost dies in some cases. Seems to be temperature related because it seems to get worse as the engine warm up.

From what I read the EGR is disabled when MAF is unplugged, hence why I thought it's an EGR issue.

[glend]

The pause at 1400rpm sounds like a turbo vane advance issue, it might be the turbo vacum controller. Do you have any codes appearing? Do you have a code reader or access to one? Might be worth getting an auto sparky or mechanic to plug his code reader in to the obdii port and see what's there.

Darren, any suggestions?

[KJ75]

There were no codes when MAF is plugged in, only when I unplug it.
I have a bluetooth 4.0 OBD reader I got from Jaycar but having issues getting it to work with the Torque Android App. The only thing it shows is the revs, but says there are no fault codes (there should be since the MAF is unplugged).

I read unplugging the MAF was a common procedure people were doing since it disables the EGR.

[KJ75]

Ok, managed to get my code reader to work.
While the MAF is unplugged, it simply shows P0102 -Powertrain Mass Volume Air Flow Circuit.

There are no codes when I plug in the MAF.

Fuel consumption is the same 7.4 litres /100 cruising at 100km/h. Fuel consumption is the same regardless if MAF is plugged in or not.

There is absolutely no smoke and plenty of power.

[KJ75]

Just a quick correction, the acceleration pause / blip is at low revs like 900 rpm.

[KJ75]

I had a look at my air box (see attached picture), and to me it seems the air box is possibly missing a metal bracket. Can anyone confirm if it is in fact missing.