• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Explorer ST Forum and Explorer ST community dedicated to Explorer ST owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the Explorer ST Forum today!


Odd sound only in sport

powerboatr

Member
U.S. Navy Veteran
Messages
461
Reactions
294
Points
67
Location
Texas
Vehicle
2023 Explorer ST
#1
I was setting up my Bluetooth obd mx plus
Scanning through pids for display on an unused phone
Anyway radio off, ac off
Sitting in driveway engine running up to 179 f
I put car in towhaul to see if it changed some pid locations in a menu
But when I selected sport
Car in N. Park brake on
I hear a weird continuous different bnoise
Came from under car.
I rolled down window and recorded it woth phone

If I didn't know better ..i would say it sounded like it opened a valve in a muffler or something , not a hiss, but like a valve opened direction the noise through a different route
I have stock exhaust
I tried uploading the sound
But it won't upload
It reminds me of when I switch on exhaust brake on my 8.3 isc engine ..
 

Last edited:
Messages
1,586
Reactions
1,154
Points
262
Location
Chicago, IL, USA
#2
I was setting up my Bluetooth obd mx plus
Scanning through pids for display on an unused phone
Anyway radio off, ac off
Sitting in driveway engine running up to 179 f
I put car in towhaul to see if it changed some pid locations in a menu
But when I selected sport
Car in N. Park brake on
I hear a weird continuous different bnoise
Came from under car.
I rolled down window and recorded it woth phone

If I didn't know better ..i would say it sounded like it opened a valve in a muffler or something , not a hiss, but like a valve opened direction the noise through a different route
I have stock exhaust
I tried uploading the sound
But it won't upload
It reminds me of when I switch on exhaust brake on my 8.3 isc engine ..
Lots of mechanical and electrical noises on this car for sure!

Only thing I hear sounding like you describe is on cold starts. Amplified with an exhaust. Seems to be three stages. First good and rumble when I start, then after about 15-20 seconds it kicks down a bit quieter, then another 15-20 seconds it drops down to normal. Definitely something changing the sound. Could just be fuel enrichment at start I suppose.

Don’t know if the turbos have anything to do with it but when I did my downpipes I noticed something at the exit of the turbos. Might have just been the top of the impeller or some type of valve. I didn’t really pay any attention to it other than noticing it before I put the DPs on.


Sent from my iPad using Tapatalk
 

OP
P

powerboatr

Member
U.S. Navy Veteran
Messages
461
Reactions
294
Points
67
Location
Texas
Vehicle
2023 Explorer ST
Thread Starter #3
This way past normal start
Engine was warm. Had been running overv10 minutes some at high idle
Then normal idle
As I was lookfor trsns temp to load gauge on android phone
I can see it in forscan..but having a tough one to find it in the same pids
So I was switching modes to see if it showed up..that's when I heard it from outside
 

Messages
4,511
Reactions
5,311
Points
352
Location
Houston, TX, USA
#4
Trans pressure changes in Sport mode…I’d guess you heard the pump when that happened. Perfectly normal.
 

OP
P

powerboatr

Member
U.S. Navy Veteran
Messages
461
Reactions
294
Points
67
Location
Texas
Vehicle
2023 Explorer ST
Thread Starter #5
Thanks it's quite noticeable
But isn't the pump running if engine is on
It really sounds like the variable exhaust vanes in a 6.7 super duty
When it tries to build a bit of positive boost right off idle
I will stop wearing my hearing aid. I heard all kinds of stuff:eek:
 

OP
P

powerboatr

Member
U.S. Navy Veteran
Messages
461
Reactions
294
Points
67
Location
Texas
Vehicle
2023 Explorer ST
Thread Starter #6
Went out hood open
Phone near left engine bank
Then sport same place..sounds like timing changed??if you did old school twist of distributor
 

OP
P

powerboatr

Member
U.S. Navy Veteran
Messages
461
Reactions
294
Points
67
Location
Texas
Vehicle
2023 Explorer ST
Thread Starter #8
Weird.. but
I accept that
Wife said ......no more hearing aid wearing in her car:ROFLMAO:
 

Cruising68

1000 Post Club
Messages
1,586
Reactions
1,154
Points
262
Location
Chicago, IL, USA
#9
Curious about the trans pump. I don’t believe it’s a variable vane pump and it spins at engine rpm so it shouldn’t sound any different. Increasing line pressure for sure happens in sport mode but I understood that to be done in electronics.

Thoughts?


Sent from my iPhone using Tapatalk
 

UNBROKEN

4000 Post Club
Messages
4,511
Reactions
5,311
Points
352
Location
Houston, TX, USA
#10
Curious about the trans pump. I don’t believe it’s a variable vane pump and it spins at engine rpm so it shouldn’t sound any different. Increasing line pressure for sure happens in sport mode but I understood that to be done in electronics.

Thoughts?


Sent from my iPhone using Tapatalk
It’s the pump. It’s been discussed ad nauseam in basically every ST group on the planet.
 

Cruising68

1000 Post Club
Messages
1,586
Reactions
1,154
Points
262
Location
Chicago, IL, USA
#11
Ok, I’ll take your word for that. More interested in what is going on in the pump to make the noise change.


Sent from my iPhone using Tapatalk
 

OP
P

powerboatr

Member
U.S. Navy Veteran
Messages
461
Reactions
294
Points
67
Location
Texas
Vehicle
2023 Explorer ST
Thread Starter #12
It’s the pump. It’s been discussed ad nauseam in basically every ST group on the planet.
I read some stuff on it..late last night
It has to do with ASS system to keep pressure up when engine shuts off, so it's ready when it refires..
Funny thing is my f150 does not do it in sport??
 



Top