OBD-II code · Powertrain (generic, extended)

P2108 Throttle Actuator Control Module Performance

Self-tests within the TAC module fail their performance criteria — for example RAM/ROM checks or analog reference voltages drift. Indicates an aging ECU rather than a wiring fault.

Is it safe to drive with P2108?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyECU internal performance fault
  • Less likelyECU connector pins corroded
  • Less likelyModule software outdated, reflash may resolve

Symptoms

  • Check engine light on
  • Reduced throttle response, possible limp mode
  • Hesitation or surging
  • Idle too high or too low

Repair at a glance

Difficulty
Hard
DIY friendly
Best left to a mechanic
Typical labour
1–4 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Ecm

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.