Subaru 1988 MPFI Fuel injected models DTC 21 – Coolant temperature sensor or circuit
DTC 21 meaning on Subaru 1988 MPFI Fuel injected models
DTC 21 indicates a problem with the coolant temperature sensor or its circuit in Subaru 1988 MPFI Fuel injected models.
Subaru 1988 MPFI Fuel injected models DTC 21 symptoms
- Engine running too cold or too hot
- Poor fuel economy
- Check Engine Light illuminated
Subaru 1988 MPFI Fuel injected models DTC 21 causes
- Defective coolant temperature sensor
- Wiring or connector issues in the sensor circuit
- Corrosion or poor connections
Subaru 1988 MPFI Fuel injected models DTC 21 seriousness
DTC 21 can lead to incorrect engine temperature readings, affecting fuel delivery and overall engine performance. It should be addressed promptly to prevent potential engine damage.
How to diagnose DTC 21 on Subaru 1988 MPFI Fuel injected models
- Check coolant temperature sensor resistance
- Inspect sensor wiring and connectors for damage
- Use a scan tool to monitor coolant temperature readings
How to fix DTC 21 on Subaru 1988 MPFI Fuel injected models
- Replace faulty coolant temperature sensor
- Repair or replace damaged wiring or connectors
- Clear DTC 21 code after repairs
How to erase DTC 21 on Subaru 1988 MPFI Fuel injected models
- Use an OBD-II scanner to clear the trouble code
- Disconnect the battery for a few minutes to reset the ECU
Recommended tools for Subaru 1988 MPFI Fuel injected models diagnostics
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Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
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