BRZg2/GR86 Tuning Troubleshooting
P0606 Fault code under acceleration
As far as we understand at the moment this code is triggered by some form of torque and throttle plausibility check. It can be disabled using the map currently named "m1d_3752a". By default it is set to 90 in most of the ROMs we have seen. Setting it to 0 worked to prevent this code coming up in a number of calibrations during testing.
Fueling going lean under boost at higher RPM
On cars with turbo / supercharger conversions you can max out the factory load limits. This will cause the fuelling to lean out as it imposes an artificially low cap on the amount of fuel that can be delivered. We have found a couple of ways to address this:
Raise the “DI Quantity Max Allowed” map. This will allow more fuel to be pushed through the DI system at higher RPM where the cam driven pump has spare capacity.
Raise the “Engine load limit 1 & 2” maps. These appear to be the ceiling value for the calculated engine load from which the fuelling requirements are calculated.
These two changes should be sufficient to run low boost and fuel correctly until you reach the reading limit of the stock MAF sensor or you max out part of the stock fuel system.
“Why does my AutoBlip not work in 2nd Gear?“
The autoblip is meant for downshifting and the latest version doesn’t blip in 2nd because people don’t generally downshift to 1st. It’s an attempt to prevent the burble from interfering with the autoblip and vice versa. The system was designed to burble in 1st and 2nd, and blip in 3rd to 6th. But that went out the window when tuners wanted burble in all gears.
Engine speed doesn’t drop when lifting off the accelerator pedal aka Rev Hang
This behaviour is usually driven by a minimum airflow type of control that will hold the throttle open and prevent the engine slowing down. This is often done to control excessive crankcase vacuum so care must be taken when trying to address this behaviour so that you do not force the throttle to shut so quickly that manifold vacuum becomes high enough to draw oil out of the sump and into the engine.
In the BRZ Gen2 / GR86 these maps are labelled as “Desired Overrun Mass Airflow”
Reducing the values in the bottom right corner as highlighted above should mean less throttle angle and a stronger engine braking effect but make small changes and monitor the intake manifold pressure.
Accelerator pedal input delay and filtering
Essentially the slow throttle response is a deliberate throttle mapping choice from the factory. This is factory strategy and the maps controlling it have been defined for some time for editing in the suite. It's only now people have finally worked out which ones control this behaviour.
At present the controls are labelled as “m3d_10_007” and numbered from 790 to 797 in most ROMs. You will find them under the “Throttle” category.
The throttle input filtering control that can be altered to reduce its effect or remove the filtering all together by changing the maps to a value of up to 1.00. A value of 1.00 means no throttle input filtering at all, a value of 0.00 would be the maximum amount of filtering. Care should be taken when setting these maps rather than just blanket setting a high value as this may make the car very twitchy at low speed if it is increased too far at low RPMs and low speeds.
Bench flashing ECU wiring diagram
This diagram can be used to wire an EVI-USB cable or EVI-BT/BTLE to the ECU for flashing out of the vehicle.
Table of Contents