new thermostat: is it me, or is it really happening? - BMW M5 Forum and M6 Forums
E39 M5 and E52 Z8 Discussion 1998-2003 Advertiser's Forum

 
LinkBack Thread Tools Rate Thread Display Modes
post #1 of 8 Old 11th April 2009, 05:49 PM Thread Starter
s328
Member, Sport: Off DSC: On (>50 posts)
 
s328's Avatar
 
Join Date: Nov 2007
Location: Alexandria VA
Posts: 96
Thanks: 18
Thanked 1 Time in 1 Post
Question new thermostat: is it me, or is it really happening?

Hi, I know that t-stat replacing is pretty common so I wanted to share an observation and ask for your opinion on it. I changed my t-stat 2 days ago (thanking M5board for very detailed description of how to do it and what can go wrong with O-ring) and almost instantly felt that car has changed. Before that my car was running pretty "cool": 76-78C with 3,000-3,500 rpm on 45 - 55 mph (not exceeding the speed limit ) Now, after I have changed the t-stat, my car under the same conditions shows 84 - 88C and according to my "butt-o-meter", it FEELS more powerful in terms of responsiveness, acceleration and "speed happiness". I know that S62 engine has several "limp modes", so my question is this: do you think that feeling "cool", DME was putting the engine in one of those modes, perventing it from unleashing more power? Thank you and happy motoring

2000 LeMans Blue M5
EVOLVE'd, waiting for the SS exhaust
1998 328: Bilstein PSS9 coilovers,
K&N CAI, Shark Injector, Sport Exhaust
and some other "toys"
s328 is offline  
Sponsored Links
Advertisement
 
post #2 of 8 Old 12th April 2009, 09:09 PM
TMcNasty
M5 Guru (>2000 posts)
 
TMcNasty's Avatar
 
Join Date: Jul 2008
Location: Ewing, NJ
Posts: 3,153
Thanks: 403
Thanked 498 Times in 344 Posts
Quote:
Originally Posted by s328 View Post
do you think that feeling "cool", DME was putting the engine in one of those modes, perventing it from unleashing more power?
No. But at some point the S62 (and any engine really) that sees a "cool" motor will richen the mixture to try and warm the motor up to operating temperature. A rich (or lean) mixture is not as efficient as the proper mix so you lose power.

You may gain power if you go just a bit lean, but a real lean mix is very bad. Best to get the mix right.
TMcNasty is offline  
post #3 of 8 Old 13th April 2009, 03:12 AM
DouglasABaker
M5 Expert (>4000)
 
DouglasABaker's Avatar
 
Join Date: Jan 2007
Location: Franklin, MA
Age: 41
Posts: 6,341
Blog Entries: 6
Thanks: 67
Thanked 2,391 Times in 942 Posts
84-88C seems awfully high for a 79C thermostat - are you sure you weren't reading the Oil temp?

d-
DouglasABaker is offline  
post #4 of 8 Old 13th April 2009, 04:17 PM Thread Starter
s328
Member, Sport: Off DSC: On (>50 posts)
 
s328's Avatar
 
Join Date: Nov 2007
Location: Alexandria VA
Posts: 96
Thanks: 18
Thanked 1 Time in 1 Post
Quote:
Originally Posted by DouglasABaker View Post
84-88C seems awfully high for a 79C thermostat - are you sure you weren't reading the Oil temp?

d-
I got 88 when it was pretty hot and I was stuck in traffic. During the weekend I continued monitoring my temp and it was 79 - 81 (82 in several occasions) under normal driving conditions ~3,000 - 3,500 rpm @ 50 - 60 mph. Thank you for pointing this out.

2000 LeMans Blue M5
EVOLVE'd, waiting for the SS exhaust
1998 328: Bilstein PSS9 coilovers,
K&N CAI, Shark Injector, Sport Exhaust
and some other "toys"
s328 is offline  
post #5 of 8 Old 13th April 2009, 04:20 PM Thread Starter
s328
Member, Sport: Off DSC: On (>50 posts)
 
s328's Avatar
 
Join Date: Nov 2007
Location: Alexandria VA
Posts: 96
Thanks: 18
Thanked 1 Time in 1 Post
Quote:
Originally Posted by TMcNasty View Post
No. But at some point the S62 (and any engine really) that sees a "cool" motor will richen the mixture to try and warm the motor up to operating temperature. A rich (or lean) mixture is not as efficient as the proper mix so you lose power.

You may gain power if you go just a bit lean, but a real lean mix is very bad. Best to get the mix right.
Thank you. Yes, I was noticing that in the morning during a quick warm-up the exhaust smelled richer than it should and now it smells not that rich.

2000 LeMans Blue M5
EVOLVE'd, waiting for the SS exhaust
1998 328: Bilstein PSS9 coilovers,
K&N CAI, Shark Injector, Sport Exhaust
and some other "toys"
s328 is offline  
post #6 of 8 Old 13th April 2009, 04:28 PM
avlnch
Moderator
 
avlnch's Avatar
 
Join Date: Oct 2007
Location: South FL
Posts: 2,200
Thanks: 166
Thanked 409 Times in 251 Posts
Quote:
Originally Posted by s328 View Post
Thank you. Yes, I was noticing that in the morning during a quick warm-up the exhaust smelled richer than it should and now it smells not that rich.
Sniffing your exhaust = and then you'll look like while everyone else is so be careful.

Later

2013 BMW ///M5 INDIVIDUAL {Frozen Black/Amaro Brown/Amaro Brown Alcantara/Piano Black Trim/Contrast Stitching}
~Mods: Akrapovic Exhaust, OEM Charcoal Filter Delete, P3 Vent Gauge, DINAN Pedals

~Mods: BMW Individual Exterior Equipment, Frozen Black Reflectors
Other Vehicles: '12 MERC S63 AMG [WHITE], '11 MERC S65 AMG [BLUE]
Previous Vehicles: '10 INDIVIDUAL BMW M5, '09 MERC S65 AMG, '08 BMW M5, '08 MERC S63 AMG, '07 BMW ALPINA B7, '06 RANGEROVER S/C
avlnch is offline  
post #7 of 8 Old 13th April 2009, 04:31 PM Thread Starter
s328
Member, Sport: Off DSC: On (>50 posts)
 
s328's Avatar
 
Join Date: Nov 2007
Location: Alexandria VA
Posts: 96
Thanks: 18
Thanked 1 Time in 1 Post
Quote:
Originally Posted by avlnch View Post
Sniffing your exhaust = and then you'll look like while everyone else is so be careful.

Later
well, all ABC's in the area were closed, so had no other choice Highly recommended when the timing is the issue Cheers

2000 LeMans Blue M5
EVOLVE'd, waiting for the SS exhaust
1998 328: Bilstein PSS9 coilovers,
K&N CAI, Shark Injector, Sport Exhaust
and some other "toys"
s328 is offline  
post #8 of 8 Old 13th April 2009, 06:12 PM
DouglasABaker
M5 Expert (>4000)
 
DouglasABaker's Avatar
 
Join Date: Jan 2007
Location: Franklin, MA
Age: 41
Posts: 6,341
Blog Entries: 6
Thanks: 67
Thanked 2,391 Times in 942 Posts
Quote:
Originally Posted by s328 View Post
I got 88 when it was pretty hot and I was stuck in traffic. During the weekend I continued monitoring my temp and it was 79 - 81 (82 in several occasions) under normal driving conditions ~3,000 - 3,500 rpm @ 50 - 60 mph. Thank you for pointing this out.
that sounds normal...
DouglasABaker is offline  
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the BMW M5 Forum and M6 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes Rate This Thread
Linear Mode Linear Mode
Rate This Thread:



Similar Threads
Thread Thread Starter Forum Replies Last Post
Valentine One - why is this happening? billrM5 E39 M5 and E52 Z8 Discussion 6 13th November 2005 02:58 AM
WTF is happening to me? phillym5 E39 M5 and E52 Z8 Discussion 39 12th August 2005 10:17 PM
What is Happening ?? atlantisvip E39 M5 and E52 Z8 Discussion 15 14th September 2004 11:52 AM
what is happening??????????? phillym5 E39 M5 and E52 Z8 Discussion 7 4th December 2002 12:12 AM

Posting Rules  
You may post new threads
You may 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 On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome