I've been hearing an intermittent ticking noise in my 2015 Subaru WRX that I can't seem to pinpoint.
The car is bone stock with ~45k miles on it and is still under warranty, but I'd rather not spend half a day waiting around without my car only to get a "could not reproduce" from the dealership.
Description of Noise
- The noise has gotten worse since I started hearing it, and now that I can hear it better, it appears to correspond (at least somewhat) with engine speed.
- I'd estimate the frequency to vary from around 2-6Hz.
- It sounds like it is coming from the engine compartment.
When It Occurs
- It only manifests itself during/shortly after the engine has been under more than a slight load (enough load that the turbo is creating positive pressure in the intake i.e. >0lb of boost).
- I can hear it when cruising/accelerating around 2K-4K RPM.
- It is drowned out by engine and exhaust noise above that point.
- I can hear it for the following 60sec or so of decelerating or coasting.
- I can't hear it at idle but can occasionally hear it when the car is parked and revved up then allowed to spin down (i.e.: accelerator flat on the floor from idle to 4k RPM, then fully released).
The noise is not there every drive:
- I initially heard it Monday.
- I didn't hear it all yesterday.
- I heard it this morning on my way to work (after about 45 minutes of highway driving).
- Once it started making the noise, it didn't stop until I parked (about 10 minutes of city driving).
Diagnostics
- It immediately vanishes when disengaging the clutch (pushing down on the clutch pedal), but returns when the clutch is re-engaged.
- Engine temperature doesn't seem to matter, it made the noise immediately after starting.
Questions
- What could be causing this?
- How do I further diagnose this?
Resolution
Took it to the dealer on 28 Nov, they looked at it and are replacing the clutch and throwout bearing.