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Hissing Sounds

Hissing Sounds Coming From Your Engine


Symptom:A hissing sound is heard from the engine. The engine may or may not seem to run well. A hissing noise like air or steam can be heard coming from the engine. A performance drop may be noticed immediately after the noise begins.

Possible causes:

  1. The engine is overheating.
    The Fix: Check and repair cooling system.
  2. The exhaust system and/or catalytic converter is plugged.
    The Fix: Check and replace exhaust system and/or catalytic converter as required.
  3. A vacuum line is leaking or disconnected.
    The Fix: Reconnect vacuum line. Replace vacuum lines if broken.
  4. A vacuum device is leaking.
    The Fix: Replace vacuum device.

Return to Engine Troubleshooting Index

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  5. Engine Troubleshooting
  6. Diagnosing Engine Problems by Sound: Hissing Sound

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