Blocked catalytic converter
- Symptoms
- Shaking in D/R at idle, weak uphill, worse with A/C, fuel economy <8 km/L
- Likely cause
- Clogged close-coupled converter
- Fix
- Clean or replace converter; check engine mounts
- Applies to
- KGC10/KGC15/QNC10; Boon M300S/M301S/M310S (same platform)
- Related fault codes
- P0420 (generic, NOT in factory DTC chart - low conf); lean/rich codes possible
- Related part numbers
- 25051-B1051
- Confidence
- medium (one thread, two owners report same fix)
Sources
Related problems on this car
- A/C load: idle vibration & poor pick-up with A/C on
- Stalling at idle with A/C + brake, hard start
- No power to fuel pump (KGC10 1KR)
- Throttle body carbon fouling
Similar problems on other cars
- Ignition coil-on-plug failure / misfire · Toyota Corolla (9th gen, E120)
- Engine noise and vibration in Drive · Toyota Corolla (10th gen, E140)
Where the parts are · Warning lights · Fault codes · Maintenance
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