Notices
LS - 4th Gen (2007-2017) Discussion topics related to the current flagship models LS460, LS460L and LS600H

Thump Sound when starting cold engine

Thread Tools
 
Search this Thread
 
Old May 18, 2016 | 06:40 AM
  #1  
UZ214's Avatar
UZ214
Thread Starter
Pole Position
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2006
Posts: 2,669
Likes: 223
From: DE
Default Thump Sound when starting cold engine

For last couple of days the car is making a Thump sound when the engine turns over. then it gone- single thump sound....It only happens in the morning if the car is sitting in the garage overnight. I do not hear it if i park the car at work after 8 hours does not make the same sound.

I also feel it takes a bit tad longer to start the car(again only in the morning)- i thought it was the battery but the battery has been replaced 2 years ago.

i will try to record the sound tomorrow and post it. the car is fine once started no funny sounds or anything. Its a 2011 with 71k miles on it.
Reply
Old May 19, 2016 | 02:26 PM
  #2  
droclex's Avatar
droclex
Pit Crew
 
Joined: Apr 2016
Posts: 175
Likes: 19
From: IL
Default

Originally Posted by UZ214
For last couple of days the car is making a Thump sound when the engine turns over. then it gone- single thump sound....It only happens in the morning if the car is sitting in the garage overnight. I do not hear it if i park the car at work after 8 hours does not make the same sound.

I also feel it takes a bit tad longer to start the car(again only in the morning)- i thought it was the battery but the battery has been replaced 2 years ago.

i will try to record the sound tomorrow and post it. the car is fine once started no funny sounds or anything. Its a 2011 with 71k miles on it.
Curious, does your thump coincide with shifting into gear on an incline or the brake pedal?
Reply
Old May 19, 2016 | 06:08 PM
  #3  
UZ214's Avatar
UZ214
Thread Starter
Pole Position
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2006
Posts: 2,669
Likes: 223
From: DE
Default

dont think so, its coming right from the front of the car-the car is not on a incline at all.

i had the camera on today but no sound. Does not sound like brake but who knows, i need brakes soon that job i will tackle on the weekend.

I did read about similar noises in different forums (acura)(ford) which they are talking about the ac making that noise. Today when i started car i had the air off yesterday. Today i will leave it on just to see.
Originally Posted by droclex
Curious, does your thump coincide with shifting into gear on an incline or the brake pedal?
Reply
Old May 20, 2016 | 03:06 AM
  #4  
whitewater's Avatar
whitewater
Driver School Candidate
 
Joined: Apr 2016
Posts: 25
Likes: 5
From: Ohio
Default

Originally Posted by droclex
Curious, does your thump coincide with shifting into gear on an incline or the brake pedal?
mine does a similar noise however I would not call it a thump. mine is the auto parking brake/electronic brakes.

interested if you get a video of this happening.
Reply
Old May 20, 2016 | 11:03 AM
  #5  
UZ214's Avatar
UZ214
Thread Starter
Pole Position
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2006
Posts: 2,669
Likes: 223
From: DE
Default

that's good point might be the auto brakes but i didn't hear any sound today also...its like when i am my camera ready the sound is not coming- its like you know trying to reproduce the problem at the dealership.
The temperature is also higher from last few days might be factor

Originally Posted by whitewater
mine does a similar noise however I would not call it a thump. mine is the auto parking brake/electronic brakes.

interested if you get a video of this happening.
Reply
Old May 20, 2016 | 02:50 PM
  #6  
superdenso's Avatar
superdenso
Instructor
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Nov 2014
Posts: 758
Likes: 26
From: INACTIVE
Default

I would inspect the motor mounts; the motor rocks the car on start-up...is it consistent with the rocking motion?
Reply
Old May 21, 2016 | 03:36 PM
  #7  
UZ214's Avatar
UZ214
Thread Starter
Pole Position
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2006
Posts: 2,669
Likes: 223
From: DE
Default

The sound is not consistent- infant i haven't heard it last 3 days i have started the car with my camera rolling
Originally Posted by superdenso
I would inspect the motor mounts; the motor rocks the car on start-up...is it consistent with the rocking motion?
Reply
Old May 21, 2016 | 05:33 PM
  #8  
Rhambler's Avatar
Rhambler
Lexus Test Driver
 
Joined: Nov 2015
Posts: 1,302
Likes: 17
From: CA
Default

Can you feel the thump or is it just audible?
Reply
ClubLexus Stories

Celebrating Lexus & Toyota from Around the Globe

story-0

10 Lexus Designs That Have Aged Like Fine Wine

 Verdad Gallardo
story-1

8 Tips for Improving Your Hybrid or Plug-in Hybrid's Efficiency!

 Michael S. Palmer
story-2

10 Best Lexus Models No One Remembers

 Joe Kucinski
story-3

TRD Off-Road Premium: Best 2026 4Runner, Except This One Thing

 Michael S. Palmer
story-4

Top 10 Lexus & Toyotas to Drive Before You Die!

 Joe Kucinski
story-5

Top 10 Lexus/Toyotas With The LEAST 5-Year Depreciation

 Joe Kucinski
story-6

Lexus LC500 Convertible Auction: A Preview of Rising Values?

 Brett Foote
story-7

GX 550 vs TX 550: Best 3-Row Luxury Lexus Family Hauler

 Michael S. Palmer
story-8

9 Best Lexus Models You Can Buy for Half Price (And 1 You Shouldn't!)

 Joe Kucinski
story-9

2026 Lexus NX Buyer's Guide: Models, Features, Prices & More!

 Brett Foote
Old May 22, 2016 | 08:24 PM
  #9  
UZ214's Avatar
UZ214
Thread Starter
Pole Position
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2006
Posts: 2,669
Likes: 223
From: DE
Default

its a mixture of both, almost seems like the engine or belts have a hard time to turn over. I also recently had 70k service done at the dealer
it might be the serpentine belt?
Originally Posted by Rhambler
Can you feel the thump or is it just audible?
Reply
Old May 23, 2016 | 04:18 AM
  #10  
Rhambler's Avatar
Rhambler
Lexus Test Driver
 
Joined: Nov 2015
Posts: 1,302
Likes: 17
From: CA
Default

Personally, I think it's just your battery.

Batteries don't last long in this day and age of modern cars and frankly they cause a lot of issues while people search for less obvious problems when the real one one is discounted because they assume it's not bad.

Now of course, I'm just guessing, but I've never seen issues with the starter (at least I can't recall seeing anyone report anything here) and a bad belt wouldn't necessarily cause the slow turnover, but a slowly dying battery will.

I think we all hear that "thump," but a good battery and starter causes the cranking to happen with normal speed. Slow it down and everything, the noise and feel, becomes more pronounced.

If you're willing to gamble on a haunch, replace the battery and see if it goes away, but again, I'm guessing.
Reply
Old May 24, 2016 | 02:46 AM
  #11  
whitewater's Avatar
whitewater
Driver School Candidate
 
Joined: Apr 2016
Posts: 25
Likes: 5
From: Ohio
Default

Originally Posted by Rhambler
Personally, I think it's just your battery.

Batteries don't last long in this day and age of modern cars and frankly they cause a lot of issues while people search for less obvious problems when the real one one is discounted because they assume it's not bad.

Now of course, I'm just guessing, but I've never seen issues with the starter (at least I can't recall seeing anyone report anything here) and a bad belt wouldn't necessarily cause the slow turnover, but a slowly dying battery will.

I think we all hear that "thump," but a good battery and starter causes the cranking to happen with normal speed. Slow it down and everything, the noise and feel, becomes more pronounced.

If you're willing to gamble on a haunch, replace the battery and see if it goes away, but again, I'm guessing.
x2 - had not thought of this but very likely.
Reply
Old May 24, 2016 | 06:38 AM
  #12  
UZ214's Avatar
UZ214
Thread Starter
Pole Position
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2006
Posts: 2,669
Likes: 223
From: DE
Default

Very well be- I will change battery and update you guys
Originally Posted by whitewater
x2 - had not thought of this but very likely.
Reply
Old May 24, 2016 | 05:44 PM
  #13  
whitewater's Avatar
whitewater
Driver School Candidate
 
Joined: Apr 2016
Posts: 25
Likes: 5
From: Ohio
Default

Originally Posted by UZ214
Very well be- I will change battery and update you guys
should have it checked - cold cranking amps and voltage etc...
Reply
Old May 24, 2016 | 05:49 PM
  #14  
UZ214's Avatar
UZ214
Thread Starter
Pole Position
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2006
Posts: 2,669
Likes: 223
From: DE
Default

Lexus did check it when they had the car @70k service- they checked the tires brakes fluids battery etc
It has some after market battery though not the OEM lexus one
Originally Posted by whitewater
should have it checked - cold cranking amps and voltage etc...
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
wickedt
LS - 4th Gen (2007-2017)
10
Dec 26, 2023 12:29 PM
jlex234
GX - 1st Gen (2003-2009)
1
Jul 8, 2018 02:38 PM
DND
GS - 2nd Gen (1998-2005)
25
Mar 17, 2013 04:06 PM
ahohnstein
IS - 2nd Gen (2006-2013)
2
Apr 19, 2007 07:55 AM




All times are GMT -7. The time now is 07:53 AM.

story-0
10 Lexus Designs That Have Aged Like Fine Wine

Slideshow: Some luxury cars chase trends, but these Lexus models look better now than they did when they first rolled into showrooms.

By Verdad Gallardo | 2026-05-06 17:58:29


VIEW MORE
story-1
8 Tips for Improving Your Hybrid or Plug-in Hybrid's Efficiency!

Slideshow: How to Get the Best Fuel Economy with a Hybrid and Plug-In Hybrid!

By Michael S. Palmer | 2026-05-05 20:54:44


VIEW MORE
story-2
10 Best Lexus Models No One Remembers

Slideshow: 10 best Lexus models no one remembers.

By Joe Kucinski | 2026-05-05 17:33:28


VIEW MORE
story-3
TRD Off-Road Premium: Best 2026 4Runner, Except This One Thing

Slideshow: diving into 4Runner TRD Off-Road Premium's pricing, performance, fuel economy, features, and amenities!

By Michael S. Palmer | 2026-04-23 13:09:18


VIEW MORE
story-4
Top 10 Lexus & Toyotas to Drive Before You Die!

Slideshow: the 10 Lexus and Toyota vehicles you need to drive before you die.

By Joe Kucinski | 2026-04-23 10:34:24


VIEW MORE
story-5
Top 10 Lexus/Toyotas With The LEAST 5-Year Depreciation

Slideshow: Top 10 Lexus/Toyota models with the lowest 5-year depreciation rate.

By Joe Kucinski | 2026-04-08 12:19:06


VIEW MORE
story-6
Lexus LC500 Convertible Auction: A Preview of Rising Values?

The LC hasn't even disappeared from the Lexus lineup yet, and we're already seeing signs of an explosive market.

By Brett Foote | 2026-04-06 09:25:02


VIEW MORE
story-7
GX 550 vs TX 550: Best 3-Row Luxury Lexus Family Hauler

Slideshow: comparing the pricings, specs, power, fuel economy, fun-factor, and features of the GX 550 Luxury+ and TX 550h+ Luxury.

By Michael S. Palmer | 2026-03-19 13:44:11


VIEW MORE
story-8
9 Best Lexus Models You Can Buy for Half Price (And 1 You Shouldn't!)

Slideshow: 9 best Lexus models you can buy for half price and 1 you should avoid

By Joe Kucinski | 2026-03-19 12:01:07


VIEW MORE
story-9
2026 Lexus NX Buyer's Guide: Models, Features, Prices & More!

Here's everything you need to know about the latest NX.

By Brett Foote | 2026-03-19 11:56:59


VIEW MORE