### P0420 Catalyst System Efficiency Below Threshold
– Frequent Reasons:
Exhaust leaks [1]
– Recommended Fixes:
Diagnose fuel trim https://carautorepair.site/
### P0171 Fuel Mixture Imbalance
– Likely Problems:
Vacuum leaks
– Testing Procedure:
Smoke test intake [1][7]
—
## Vehicle Service Vocabulary
### Skid Prevention Technology
– Function: Enables safe braking [7]
### Engine Management Unit
– Responsibility: Controls ignition timing [7]
### Transmission System Parts
– Contains: Transmission [7]
—
## Service Procedure Stages
1. **Symptom Assessment**:
Conduct road test
2. **System Verification**:
Check voltage
3. **Component Installation**:
Use OEM parts
4. **System Validation**:
Ensure proper operation
—
## Critical Instruments
| **Tool Type** | **Examples** | **Purpose** |
|—|—|—|
| Diagnostic Scanner | Autel | Retrieve DTCs |
| Physical Equipment | Multimeter | Component repair |
—
## Repair Documentation Sources
### Auto Repair Source
– Features:
Wiring diagrams [8]
Technical illustrations
### Digital Assistants
– Auto Repair Documents:
ECU pinouts [5]
—
## Cost-Saving Tips
– Preventative service prevents major failures
– Understand DTC meanings to avoid unnecessary repairs
– Install quality alternatives when budget constrained [7]
