Welcome to the North American Subaru Impreza Owners Club Sunday February 28, 2021
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > FA Series Factory 2.0L Turbo Powertrain

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 01-21-2021, 08:06 PM   #1
Starcrafter
Scooby Newbie
 
Member#: 365071
Join Date: Aug 2013
Default FA20DIT 2016 whomping noise at 900-1000rpm


I'm trying to understand which part of the engine does this nasty whomping at 900 to 100rpm.

Long story short. Got a new WRX in September 2016 (MY17). When the odometer was at around 20k (12500 miles) km I noticed a whopping noise above idle rpm which was disappearing once oil temp was hitting 30C (86F). After about 6-7 months and another 5k km (3k miles) the noise became permanent and can be heard at any engine temp.

I visited the dealership numerous times but they don't know what it is. We fired up a few other WRXs with different mileages ranging from 0 to 40k km. The new vehicle didn't have it. 7k km unit had it but it was really hard to hear. 40km unit had the noise but was less noisy than mine (I'm at 43k km now). All cars we checked were MY17.

Dealerships, I visited, have two versions: high-pressure fuel pump or CVT pump. I don't think it's CVT pump. You can easily hear that beast while driving the first few minutes when it's cold outside (I'm from Canada ). It sounds like a hydraulic power steering pump on older vehicles under the load.
I'm not sure about the fuel pressure pump working noise, but it's an electrical pump and its noise shouldn't be linked to engine rpm but to engine load.

I know at least one person with the same complaint. He also can't find the source of whooping.

Any ideas what it can be?
* Registered users of the site do not see these ads.
Starcrafter is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 01-23-2021, 09:28 PM   #2
vegwrx
Scooby Newbie
 
Member#: 494147
Join Date: Nov 2018
Location: Nashville, TN
Vehicle:
2017 WRX
Blue

Default

If I’m understanding your description correctly mine does it as well… I am at 81,000 miles on my 2017 and haven’t had any issues. Do you have any modifications?
vegwrx is offline   Reply With Quote
Old 01-23-2021, 10:42 PM   #3
Starcrafter
Scooby Newbie
 
Member#: 365071
Join Date: Aug 2013
Default

I removed the serpentine belt today and started the engine without it. No noise.

Then I took a stethoscope and listened to 3 possible sources: tensioner, pulley and AC compressor. The tensioner is the noisiest guy on this list. I'm still not 100% sure as it was the very first time in my life I used a stethoscope but at least I know it's not the engine and it will be an easy and not expensive fix.

I bet all WRXs have this noise. All we checked at the dealership had it. However, for the manual car it's not a big deal as you almost don't drive in that rpm range.
CVT is a different story. When the engine is still cold and you stop at traffic lights your idle at Drive will be around 1000. Same rpm if to drive very slowly at 10-12mph which happens to me every morning.
Starcrafter is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 03:10 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2021 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.