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Q: Noise coming from front left side of engine.

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I suspect I may have a issue with the timing chain guides in this engine. Please tell me the fastest and surest way to confirm this. At fast idle there is a random knocking noise coming from the area of the AC Compressor. However I have my suspicions it is not the Compressor.

My car has 70000 miles.
My car has an automatic transmission.

Hello. Most of the time when this noise occurs from this engine, it is a timing chain problem. To isolate this, I usually remove the engine drive belts and run the engine to see if the noise disappears. If it does, then it is in one of the engine pulleys. If not, then it is in the timing chain assembly and that will need to be repaired. If you need to have this knocking noise looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair this.

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