Idle hunting / stalling when the clutch is pressed (IACV/throttle body)
- Symptoms
- RPM dips to ~400 or the engine stalls when the clutch is pressed or the A/C comes on
- Likely cause
- Carbon in the throttle body / rotary IAC valve
- Fix
- Clean the throttle body and IACV; check vacuum leaks; normal idle 750-850 rpm (forum)
- Applies to
- NZE120R (2NZ) and ZZ engines with IACV
- Related fault codes
- P0505
- Confidence
- low
Sources
- pakwheels.com/forums/t/toyota-corolla-model-e-120-2002-2008-owners-and
- youtube.com/watch?v=szXydFfT7xo
- toyotanation.com/threads/idle-control-system.1768767/
- toyotamanuals.gitlab.io/RM01J1E/htmlweb/rm01j1e/rm/rm821e/m_05_0075.pd
Related problems on this car
- Ignition coil-on-plug failure / misfire
- Intake manifold gasket vacuum leak (1ZZ)
- A245E/A246E automatic (PK 1.6 = A246E): harsh/flare 2-3 shift, slips, TCC codes
- A/C compressor failure / poor cooling
Similar problems on other cars
- Idle drops or engine stalls when pressing the clutch · Suzuki Cultus (2nd gen, EFI)
- Throttle body carbon fouling · Toyota Passo (1st gen)
- RPM drops when braking with the A/C on · Honda City (5th gen, GM2)
Where the parts are · Warning lights · Fault codes · Maintenance
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