Faint chirping noise 2013 Ford Fiesta 1.0 80HP

[13Fiesta1.0_80hp]

As the title suggests, my manual 2013 Ford Fiesta 1.0 80HP (non-turbo) makes a faint chirping noise. The only time you can hear this sound is when the engine is cold and when you are lightly pressing the accelerator. This sound gets just a tiny bit louder when pressing the accelerator harder. Once the engine is warm, the sound disappears. It seems to definitely be coming from the engine bay.

Any suggestions what this sound might be?

Thanks!

 

[Handy Andy]

Several things, the "chirps" duration may be short, but if a little RPM (throttle touch) is applied, does the chirp change the duration or the the pause in-between the chirps change its frequency - rapidity or occurs faster only to slow back down to that gentle chirp when you let off the throttle?

The only reason I mention this is both the Sigma base motor 4-cylinder and the 1.0L have a similar design of using a waterpump running off the outer serpentine belt but enclosed inside a housing containing the timing belt.

That chirp may mean a squeaky water pump bearing noise that slowly follows RPM in occurrence - because the pulley is running at belt speed, but due to it's shaft being much smaller - the conversion from the belt speed to the shaft rotation RPM is a REDUCTION of about 4:1 so the belt has to travel a bit faster to even notice the noise in the chirp duration changes - but by then the engine noise can drown out the effect.

EDIT: Sorry - got pulled away...to continue

The other devices like AC and Alternator on the serpentine - will vary their chirp directly to the RPM change - so a slow change in RPM and the Chirp follows that change? Then either the AC - Alternator or the tracking of the belt across the waterpumps pulley surface - if the belt shifts or wanders the pulley surface (referring to the belt seems to want to wear the water pump pulley surface in a larger width than the belt usually would follow) - then the belt is causing the chirp and it's worn.

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So if you've got service history on it, if they have not changed the belt - best to try that route versus further in-depth diagnosis. For if the chirp returns - then at least the belt is changed so that is ruled out as the cause. If you put a lot of miles on it - then the belt change even if from a previous service job done - it will help in finding the root cause by replacing the belt - if the chirp returns or goes away - - the other methods are to help you diagnose which one of the other parts of the serpentines route are possible causes.

 

[13Fiesta1.0_80hp]

Hi @Handy Andy! Thanks for your reply. I will update you with some more information once I get the chance to hear it again. I'll also try to make a video of it.

 

[Handy Andy]

As you investigate this, you'll find the chirp doesn't seem to hit a spot repeatedly while watching the belt and engine run all the time, it's "just there" it may be internal - see if sitting inside the vehicle as it runs can help you develop a noise or growl that follows this repetition. Then the issue is internal to the engine.

The internal part then suggests more of a tranny or still possible water pump issue.

 

[SyntheticAtmosphere]

If you still cant sort it out, check to see if your spark plugs are tight... I wouldnt believe it till I experienced it myself. The car it happened on the plugs would have been installed by the factory.

 

[13Fiesta1.0_80hp]

There I am again! I managed to get a somewhat okay-ish video of the sound. At the end of the video you can hear the faint chirping sound (sorry for the wind noise).

Video

Couple of other things:
- The sound is not present when stationary and revving.
- The sound is also not present when idling.

 

[13Fiesta1.0_80hp]

If you still cant sort it out, check to see if your spark plugs are tight... I wouldnt believe it till I experienced it myself. The car it happened on the plugs would have been installed by the factory.

Oh wow that's bizarre. I'm definitely gonna check that tomorrow.

 

[Handy Andy]

It's very faint - almost like an alternator belt squeak, any tug or drift in steering?

Why? The Fiesta has a EPAS system - it doesn't use a power steering pump it uses a torque sensor array and motors to make the car steer using electrical power versus using a fluid like a power steering or a water pump.

Did you get a mechanic under there to look at your CV joints - both Left and Right? Especially Right side, see if you have a carriage bearing problem - the Axle shaft might have a carrier bearing that helps support the longer shaft the Right side is - if the bearing is weak and doing this as you drive - this might explain that.

You didn't tell us you have to drive it to hear the noise - thought you heard this while you sat at a light and could hear it thru the car - this is a bit different - this might be a wheel bearing, onto worn axle.

 

[13Fiesta1.0_80hp]

It's very faint - almost like an alternator belt squeak, any tug or drift in steering?

Why? The Fiesta has a EPAS system - it doesn't use a power steering pump it uses a torque sensor array and motors to make the car steer using electrical power versus using a water pump.

Did you get a mechanic under there to look at your CV joints - both Left and Right? Especially Right side, see if you have a carriage bearing problem - the Axle shaft might have a carrier bearing that helps support the longer shaft the Right side is - if the bearing is weak and doing this as you drive - this might explain that.

You didn't tell us you have to drive it to hear the noise - thought you heard this while you sat at a light and could hear it thru the car - this is a bit different - this might be a wheel bearing, onto worn axle.

The weird thing is that you should hear this all the time if it is a CV joint, but you only hear this when pressing the accelerator. Also, if the engine is warm, the sound is not present anymore.

My best guess indeed is to bring it to the mechanic and see if he can troubleshoot the issue.

Thanks anyways for all the information and help!

 

[SyntheticAtmosphere]

When you rectify this issue, please post up what it was and the actions taken to repair. Could be as odd as the spark plugs!

 

[Handy Andy]

Are you thinking cracked insulator or loose plug?

eww...woof, this whistle can cause a vacuum leak...

 

[SyntheticAtmosphere]

On the car I was working on ('15 Chev Cruze) it was loose plugs. I had replaced the intake manifold and cam cover and never touched the plugs. I thought I had damaged something or caused bigger problems. Glad I figured it out, I do not relish returning with my hat in my hand.

I suppose a cracked insulator could present with the same symptoms.