Sponsored

Annoying quiet rattle cold engine

Qjoh5510

Well-Known Member
First Name
Quinn
Joined
Nov 28, 2019
Threads
17
Messages
276
Reaction score
235
Location
Somewhere near Chicago, IL
Vehicle(s)
2019 JLUR
Occupation
Operator
Anyone else have a low key quick paced rattle/knocking noise when accelerating with a cold engine? The speed of the noise seems to be in line with engine rpm, goes away when the trans is shifting and comes back while accelerating through the next gear. So it’s only doing it under acceleration and for the first couple minutes when the engine is cold. The noise is totally gone after the engine warms up, maybe like 2 or 3 minutes of driving.
Sponsored

 

TravisRogers

Well-Known Member
First Name
Dan
Joined
Jun 19, 2018
Threads
20
Messages
223
Reaction score
391
Location
Annapolis, MD
Vehicle(s)
2018 Jeep Wrangler JL Sahara
My engine sounds like a diesel when it’s cold. Always makes me cringe. But it also pings when it’s warm. And it drinks oil.

You know how people would put 300K miles on an old Toyota truck and feel bad about selling it because it still ran perfectly? Yeah, this isn’t that.
 

asuperheat

Well-Known Member
First Name
Chris
Joined
Apr 20, 2021
Threads
2
Messages
144
Reaction score
189
Location
Florida
Vehicle(s)
08 JKU, 21 JLUR 392
Maybe Fuel? What grade of fuel are you using?

Kind of sounds like what you are describing is not high enough octane or older fuel that's been sitting. Try a different station and higher octane for a tank and see what it does.

Could be a knock sensor failing.
 
OP
OP
Qjoh5510

Qjoh5510

Well-Known Member
First Name
Quinn
Joined
Nov 28, 2019
Threads
17
Messages
276
Reaction score
235
Location
Somewhere near Chicago, IL
Vehicle(s)
2019 JLUR
Occupation
Operator
Maybe Fuel? What grade of fuel are you using?

Kind of sounds like what you are describing is not high enough octane or older fuel that's been sitting. Try a different station and higher octane for a tank and see what it does.

Could be a knock sensor failing.
I’ve been running mid grade which is 91 out here. My last 2 fill ups have been 93. I don’t get any pinging or knocking when warmed up. Just this quiet knocking or whatever it is when cold for the first few minutes. It is load based too. The more load I give it the heavier and louder it gets.
 

F-1shakey

Member
First Name
Andrew
Joined
May 26, 2021
Threads
1
Messages
20
Reaction score
10
Location
Ontario, Canada
Vehicle(s)
2021 Wrangler 2 Door sport
I’ve been running mid grade which is 91 out here. My last 2 fill ups have been 93. I don’t get any pinging or knocking when warmed up. Just this quiet knocking or whatever it is when cold for the first few minutes. It is load based too. The more load I give it the heavier and louder it gets.
I just posted a question regarding a similar issue with my 3.6/6speed. I’m hearing that noise aswell when accelerating cold; but I can also hear the ticking/tapping/knocking when it is coming down from fast idle to normal idle for about 5-7 seconds , are you experiencing this aswell?
 

Sponsored

OP
OP
Qjoh5510

Qjoh5510

Well-Known Member
First Name
Quinn
Joined
Nov 28, 2019
Threads
17
Messages
276
Reaction score
235
Location
Somewhere near Chicago, IL
Vehicle(s)
2019 JLUR
Occupation
Operator
I just posted a question regarding a similar issue with my 3.6/6speed. I’m hearing that noise aswell when accelerating cold; but I can also hear the ticking/tapping/knocking when it is coming down from fast idle to normal idle for about 5-7 seconds , are you experiencing this aswell?
I’m not sure about the fast to slow idle. I’ll have to check on that in the morning. You’re talking about when you first start the engine and it’s at fast idle and eventually slows down? I’ll pay attention to it in the morning and report back.
 

F-1shakey

Member
First Name
Andrew
Joined
May 26, 2021
Threads
1
Messages
20
Reaction score
10
Location
Ontario, Canada
Vehicle(s)
2021 Wrangler 2 Door sport
I’m not sure about the fast to slow idle. I’ll have to check on that in the morning. You’re talking about when you first start the engine and it’s at fast idle and eventually slows down? I’ll pay attention to it in the morning and report back.
Yes exactly, as it’s settling down to normal idle speed I’m getting the noise for 5-7 seconds
 

F-1shakey

Member
First Name
Andrew
Joined
May 26, 2021
Threads
1
Messages
20
Reaction score
10
Location
Ontario, Canada
Vehicle(s)
2021 Wrangler 2 Door sport
I’m not picking up any knocking noises during rpm slowdown after high idle warmup.
alright well thanks for checking anyways, I’m going to be bringing it to the dealer next week to get checked out.
 

Sponsored

TravisRogers

Well-Known Member
First Name
Dan
Joined
Jun 19, 2018
Threads
20
Messages
223
Reaction score
391
Location
Annapolis, MD
Vehicle(s)
2018 Jeep Wrangler JL Sahara
I run 93 in mine all the time to keep it from pinging. The manual says pinging is normal. Guess that’s easier than fixing it.
 

Steph1

Well-Known Member
First Name
Steph
Joined
Jul 21, 2021
Threads
27
Messages
1,518
Reaction score
2,084
Location
Quebec, Canada
Vehicle(s)
Jeep JLU , Audi Q5
Let your gas tank almost go empty and fill-up with premium. Could be placebo effect, but I swear mine runs quieter and smoother when I do that.
 

legacy_etu

Well-Known Member
First Name
Brian
Joined
Mar 9, 2021
Threads
0
Messages
123
Reaction score
121
Location
RI
Vehicle(s)
23 Glad. Mojave, 16 JKU Sahara, 20 Supra
Just a thought regarding premium fuel. Given the cost of gas these days it occurs to me that stations may be selling a lot less (of premium) these days. Makes me wonder if the stations are sitting on old gas . Perhaps seek out stations with high volume to minimize the chance of getting old gas .........or buy regular which everyone buys and throw in some octane boost.

Anyone ever datalog a Jeep?
Sponsored

 
 



Top