Subaru 1987 Fuel injected models DTC 21 – Coolant temperature sensor or circuit
DTC 21 meaning on Subaru 1987 Fuel injected models
DTC 21 indicates a problem with the coolant temperature sensor or its circuit in Subaru 1987 Fuel injected models.
Subaru 1987 Fuel injected models DTC 21 symptoms
- Engine running too cold or too hot
- Poor fuel economy
- Check Engine Light illuminated
Subaru 1987 Fuel injected models DTC 21 causes
- Defective coolant temperature sensor
- Corroded or damaged sensor wiring
- Poor electrical connection
Subaru 1987 Fuel injected models DTC 21 seriousness
DTC 21 can lead to incorrect fuel mixture, affecting engine performance and emissions. It should be addressed promptly to prevent further issues.
How to diagnose DTC 21 on Subaru 1987 Fuel injected models
- Check coolant temperature sensor resistance
- Inspect sensor wiring for damage
- Test sensor voltage output
How to fix DTC 21 on Subaru 1987 Fuel injected models
- Replace coolant temperature sensor if faulty
- Repair or replace damaged sensor wiring
- Ensure proper electrical connections
How to erase DTC 21 on Subaru 1987 Fuel injected models
- Use an OBD-II scanner to clear the trouble code
- If the issue is fixed, the Check Engine Light should turn off
Recommended tools for Subaru 1987 Fuel injected models diagnostics
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Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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