Hihi,

My car has previously thrown a code which indicate maximum fuel trim has reached. Since then car has not been able to maintain an idle properly.

I have worked on the car extensively in terms of clearing the carbon, changing injectors, the HPFP etc etc. No change in condition.

I have cleared the adaptation tables and the multiplicative tables (now @ factory spec) still having the same issue.

My qns : "Are the adaptation values the same thing as fuel trim settings?"

 

Maximum fuel trim would mean that the ECU is seeing too lean of mixture and has bumped up the injector duty cycle to its maximum value...
Problem is, the ECU is still seeing a lean condition...
Which means, you're pulling in unmetered air from somewhere in the intake system, or even a valve cover (they can crack / leak).

Adaptation is the ECU's way to make sure fuel trim is on par with stiochometric values.
However, there's a limited range to how much the ECU can add or take away in terms of injector pulse (duty cycle) length.

- Erik