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YOUR RESEARCHHum post long drive
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Replace ."picture curtesy of
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Hoping the sound is coming from here, easy to change."Picture curtesy of
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I went for a longish drive today in the nice Georgia weather before rain comes back tomorrow. After parking in the garage, key off and out, doors closed, I hear a faint hum coming from the engine bay. Pop the lid, cannot locate anything. It was not the air pump. It was not the engine lid fan. 2003 C2 6 speed.
It lasted 7-10 minutes post shutdown. It remained on after the dash lights went out. It even continued post locking with the remote.
It was a soft hum, loudest near the driver rear wheel area, and with the engine lid up, sounded like it was a ways back near the transaxle.
I had never heard it before. Any thoughts?
Lasting 7-10 min post shutdown seems to indicated a vent of pressure buildup due to heat. First thoughts are fuel tank vent and cooling system vent.
Take a 3-4ft piece of 3/8 flexible tubing/hose to get your ear close to the source of the noise, particularly the fuel tank vent solenoid at the rear on intake manifold, and the coolant vent on top of the coolant reservoir.
It should be distinguishable when you get the listening device close to the source, if not one of those two, I'll have to ponder some more for other suggestions.
Definitely not coolant vent on the reservoir, that is a very prominent location. The sound was further inside the engine bay, sounded more to the left front of the engine (front meaning towards front of car - IE - not near the belts/pulleys). Vehicle temps were normal - coolant was 180 on the gauge.
Can you share a part number of the fuel tank vent solenoid so I can try to see what it looks like and where located? Thanks for the response.
Hoping the sound is coming from here, easy to change."Picture curtesy of
jdbornem
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Another thought would be the vacuum canister located under the intake by the starter, a hum during leak down of vacuum.
This is a source reference. Confirm exact model applicability in the original material.
