Hi,

 

Whenever I cold start the car especially at night time I hear a loud brief electrical buzzing noise for a sec then engine sounds normal. Why is that?

 

Modern cars are mostly computer/electrical and I am afraid this may cause damage to the electrical/computer systems of the car like the ECU etc.

 

Should I be worried?

Edited 21 February, 201511 yr by very452001

Anyone know?

Bump anyone?

Nobody knows?

Hello... Echo

Is this in the first second or two of starting the engine?

 

If you then switch off the engine and restart it, does the noise reoccur?

 

Is the noise from the engine itself or from the instrument cluster?

 

Could be a camchain rattle (if its got a chain), could be a belt slipping (due to alternator load / lack of tension), if from the cluster it could be a warning buzzer - low voltage (battery) or other.

Fuel pump pressurizing the system? It would have more work to do after sitting cold overnight.

Is this in the first second or two of starting the engine?

 

If you then switch off the engine and restart it, does the noise reoccur?

 

Is the noise from the engine itself or from the instrument cluster?

 

Could be a camchain rattle (if its got a chain), could be a belt slipping (due to alternator load / lack of tension), if from the cluster it could be a warning buzzer - low voltage (battery) or other.

 

In the 1st second.

 

Noise does not re-occur.

 

From the engine compartment.

 

Definitely a electrical sound so we can rule out anything mechanical.

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Hi you there mate?

Bump urgent advice needed