Sponsored

Buzzing sound after shutdown

SCOverlander

Well-Known Member
First Name
Jeff
Joined
Jun 26, 2020
Threads
9
Messages
119
Reaction score
148
Location
Bay Area, CA
Vehicle(s)
2021 JL Rubicon Diesel
Hello JL 3.0 owners,
I finally picked up the diesel and did the 600 mile drive home. The motor is amazing. Fast, powerful, and averaged 27 mpg driving 70-80.
As soon as pulled into the driveway I noticed a buzz/hum from the engine bay after shutdown. The noise last for 3 minutes and then goes away. I do have a call into into dealer but havenā€™t heard back. I donā€™t think this is normal but donā€™t know.
Sponsored

 

Attachments

hazards280

Well-Known Member
Joined
May 17, 2017
Threads
2
Messages
60
Reaction score
99
Location
Midland MI
Vehicle(s)
22' JLUR 392 - Sarge Green
The sound you're hearing is a pump circulating coolant through the turbo and intercooler. This is done to help cool these components and prevent heat soak from causing damage.

Note, I own a Alfa Romeo Giulia (turbo as well) and it makes the exact same noise when its turned off. Other owners have asked the question and Alfa responded back with the details.
 

Oilburner

Well-Known Member
Joined
Dec 20, 2019
Threads
13
Messages
577
Reaction score
984
Location
You'll never find me
Vehicle(s)
Jeeps
The sound you're hearing is a pump circulating coolant through the turbo and intercooler. This is done to help cool these components and prevent heat soak from causing damage.
1. Thanks, I wondered what that noise was.
2. Yet another reason not to keep a vehicle more than a few years - so complicated. (Or maybe Iā€™m just getting older? OR BOTH!)
 

limeade

Well-Known Member
First Name
Guy
Joined
Oct 29, 2018
Threads
30
Messages
1,478
Reaction score
2,778
Location
Reno, NV
Vehicle(s)
2018 JLUR
Vehicle Showcase
1
1. Thanks, I wondered what that noise was.
2. Yet another reason not to keep a vehicle more than a few years - so complicated. (Or maybe Iā€™m just getting older? OR BOTH!)
This is a common cool-down procedure for modern turbo diesel engines. You WANT it to do this. Before manufacturers installed this auto cooling, you were supposed to let the engine idle for up to several minutes prior to every shut down in order to get the turbo and EGR temps back into a acceptable range. This is/was especially important after hauling heavy loads, going up steep grades, etc. Shutting down a diesel engine when the EGR temps are high will lead to a short engine life.
 

Sponsored

Killdozer

Well-Known Member
Joined
Jan 31, 2020
Threads
4
Messages
76
Reaction score
67
Location
Alabama
Vehicle(s)
JL sport
I was wondering the same thing too. I have been letting it idle for a minute or so but its nice to know that won't be needed anymore.
 

xylodan

Well-Known Member
First Name
Dan
Joined
Jun 27, 2021
Threads
7
Messages
123
Reaction score
155
Location
Henderson, NV
Vehicle(s)
2021 JLURD
Build Thread
Link
Occupation
Engineer
Hooray! Question answered using the search function. :)
I figured the noise was normal and nothing to be concerned with, but it is definitely unique to any vehicle I've had before that had more mellow sounding shut down noises.
 

Sponsored

WXman

Well-Known Member
Joined
Mar 1, 2017
Threads
61
Messages
2,855
Reaction score
3,076
Location
Central Kentucky
Vehicle(s)
2018 Wrangler Unlimited
Occupation
Meteorology and Transportation
Are we certain that's what the buzzing is? Because the sound comes from the CP4 injection pump.

Turbo cooling would make more sense, though.
 

Oilburner

Well-Known Member
Joined
Dec 20, 2019
Threads
13
Messages
577
Reaction score
984
Location
You'll never find me
Vehicle(s)
Jeeps
Digging up this thread, my diesel Wrangler has buzzed after shutoff since new (more like a hum), but today after a run to town, the buzzing is easily 5X Louder than ever before šŸ˜¬
 
  • Wow
Reactions: ECP
OP
OP
SCOverlander

SCOverlander

Well-Known Member
First Name
Jeff
Joined
Jun 26, 2020
Threads
9
Messages
119
Reaction score
148
Location
Bay Area, CA
Vehicle(s)
2021 JL Rubicon Diesel
Digging up this thread, my diesel Wrangler has buzzed after shutoff since new (more like a hum), but today after a run to town, the buzzing is easily 5X Louder than ever before šŸ˜¬
I would think if the noise is now louder then that may not be normal. Are you going to take it in?
 

Oilburner

Well-Known Member
Joined
Dec 20, 2019
Threads
13
Messages
577
Reaction score
984
Location
You'll never find me
Vehicle(s)
Jeeps
I would think if the noise is now louder then that may not be normal. Are you going to take it in?
adding some fuel treatment & topping off, will monitor- dealer wonā€™t do anything until something breaks anyway. Note: I did get fuel from an unfamiliar station last time-
 

TJ_HOOKER

Well-Known Member
First Name
Jeff
Joined
Jan 30, 2021
Threads
13
Messages
145
Reaction score
174
Location
Ontario Canada
Vehicle(s)
2021 JLU Rubicon Ecodiesel
I thought it was a cool down cycle as well but Itā€™s the fuel system. Green Diesel Engineering explained it to me that only the Jeep does this after shutting off and the Ram does not so itā€™s disabled as part of their tune.
Sponsored

 
 



Top