Go Back  MBWorld.org Forums > Mercedes-Benz SLR & SL Roadsters > SL-Class (R230)
Changing Spark Plugs 100,000 Miles >

Changing Spark Plugs 100,000 Miles

Notices
SL-Class (R230) 2003 -- 2012: Discussion on the SL500, SL550, SL600

Changing Spark Plugs 100,000 Miles

 
Old 04-10-2014, 10:22 PM
  #1  
Newbie
Thread Starter
 
SMGEO's Avatar
 
Join Date: Apr 2014
Location: Florida
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
1999 MB S420, 1993 SEC600(Awesome) 1995 SL320, Now MB SL 500
Changing Spark Plugs 100,000 Miles

Coming up on that 100,000 mile mark 2004 SL500. Mechanic quoted me $500 to change my plugs. How hard is it, does a mechanic really need to do this? Look forward to responses.
SMGEO is offline  
Old 04-11-2014, 03:52 AM
  #2  
Member
 
josephanthony's Avatar
 
Join Date: Apr 2012
Location: Hockessin, DE
Posts: 123
Likes: 0
Received 0 Likes on 0 Posts
2009 SL 550 Silver Arrow Launch Edition
Originally Posted by SMGEO View Post
Coming up on that 100,000 mile mark 2004 SL500. Mechanic quoted me $500 to change my plugs. How hard is it, does a mechanic really need to do this? Look forward to responses.
Here is a video link for a 2005 S500. Same procedure for R230, only configuration of engine compartment may vary slightly.


It took me an hour to replace mine in my former R129 SL500SA.
josephanthony is offline  
Old 04-11-2014, 04:26 PM
  #3  
Senior Member
 
Join Date: Jul 2006
Posts: 268
Likes: 0
Received 0 Likes on 0 Posts
2011 E550, 2008 SL55 AMG
Originally Posted by SMGEO View Post
Coming up on that 100,000 mile mark 2004 SL500. Mechanic quoted me $500 to change my plugs. How hard is it, does a mechanic really need to do this? Look forward to responses.
Clearance in the engine bay is fairly limited. You'll need something to pull the plug wires off - the left and right rear plug wires were a real PITA on my '08 SL55. You'll also need a plug socket, extensions, a U joint, and a good torque wrench (torque is 20 ft/lb IIRC). The process itself is fairly straightforward, and removing the coil packs makes it much easier (be sure to label the plug wires by cylinder/location as you remove them).

If I had a tool to pull the two really hard plug wires (or more grip strength) I could have done the job in two or three hours - that's all 16 plugs on an '08 SL55. If your SL500 has two plugs per cylinder, the plugs alone will cost a couple hundred bucks - skinned knuckles and frustration can easily raise the value of the service to what your mechanic is asking.
pdjv is offline  
Old 04-11-2014, 05:00 PM
  #4  
Member
 
Join Date: Feb 2014
Posts: 118
Likes: 0
Received 0 Likes on 0 Posts
SL500, Miata
Originally Posted by SMGEO View Post
How hard is it, does a mechanic really need to do this?
Easy job. Took J.A. just an hour; took me about 1-1/2 hours.

Originally Posted by pdjv View Post
...the plugs alone will cost a couple hundred bucks...
Not unless you are paying over the MSRP for them. Sixteen plugs at autohausaz.com comes to around $83, and the shipping is free.
Rod_84 is offline  
Old 04-14-2014, 01:41 PM
  #5  
Senior Member
 
Join Date: Jul 2006
Posts: 268
Likes: 0
Received 0 Likes on 0 Posts
2011 E550, 2008 SL55 AMG
Originally Posted by Rod_84 View Post
Not unless you are paying over the MSRP for them. Sixteen plugs at autohausaz.com comes to around $83, and the shipping is free.
$83 sounds awfully cheap. Autohaus AZ currently lists OE Bosch plugs for an SL550 at $15 each - that's $120 for eight. With twice as many plugs an SL55 would cost over $160 for NGK plugs and $312 for OE Bosch plugs.
pdjv is offline  
Old 04-14-2014, 02:31 PM
  #6  
Member
 
Join Date: Feb 2014
Posts: 118
Likes: 0
Received 0 Likes on 0 Posts
SL500, Miata
Originally Posted by pdjv View Post
$83 sounds awfully cheap.
Pretty good, huh? That's for an updated iridium plug. With platinum plugs the cost is just $44.

I chose the iridium.
Rod_84 is offline  
Old 04-14-2014, 04:07 PM
  #7  
Member
 
Georgee6086's Avatar
 
Join Date: Jan 2014
Location: Toronto
Posts: 202
Likes: 0
Received 3 Likes on 3 Posts
1994 E500, 2012 e63
I just did mine and the hardest part was pulling off the wires I used a set of long needle nose pliers that had a bit of a curve to them. And yes definitely mark your wires mine got mixed up and it took me forever to figure out what went where. Once you get the first 2 out it starts getting easy save your $500
Georgee6086 is offline  
Old 04-15-2014, 09:25 PM
  #8  
Member
 
Join Date: Apr 2006
Location: Bonita Springs, FL
Posts: 165
Likes: 0
Received 0 Likes on 0 Posts
2007 SL600 Designo Graphite /Black; 2015 S550 Silver
After changing out the plugs, did you notice any improvement in performance? Did the removed plugs look corroded or were they still in pretty good shape?
TwinCam is offline  
Old 04-16-2014, 11:38 AM
  #9  
Member
 
Georgee6086's Avatar
 
Join Date: Jan 2014
Location: Toronto
Posts: 202
Likes: 0
Received 3 Likes on 3 Posts
1994 E500, 2012 e63
Mine had 110000 miles when I replaced them and to be honest they didn't look too bad, the rear ones seemed to have a bit of burnt oil around the threads so I had a leak down test done and everything was within spec. The car did seem to idle a little bit better after the new plugs not much tho, I then reset all the adaptions with star and it smoothed out the idle more. I think the oil is a result of the pcv system pulling oil from valve covers. I will be adding a oil separator soon. Also I used the colder ngk's
Georgee6086 is offline  
Old 04-16-2014, 08:56 PM
  #10  
Member
 
Join Date: Apr 2006
Location: Bonita Springs, FL
Posts: 165
Likes: 0
Received 0 Likes on 0 Posts
2007 SL600 Designo Graphite /Black; 2015 S550 Silver
I only have 20,000 miles on my 2007 SL600. Lots of plugs to change. I am planning to get it done next year, so far the car still runs like a beast...the plugs must still be good.
TwinCam is offline  
Old 05-10-2016, 10:27 AM
  #11  
Senior Member
 
anothercar's Avatar
 
Join Date: Aug 2014
Location: HHI, SC
Posts: 299
Received 20 Likes on 17 Posts
2002 C4 Cab, 2014 Audi A5 cab, 2017 X5 35d
My '03 SL500 has only 23,000 miles and it runs just fine. However, at age 13 I'm wondering if I should change the plugs? What advice can y'all provide.
anothercar is offline  
Old 05-10-2016, 02:04 PM
  #12  
Member
 
josephanthony's Avatar
 
Join Date: Apr 2012
Location: Hockessin, DE
Posts: 123
Likes: 0
Received 0 Likes on 0 Posts
2009 SL 550 Silver Arrow Launch Edition
Originally Posted by anothercar View Post
My '03 SL500 has only 23,000 miles and it runs just fine. However, at age 13 I'm wondering if I should change the plugs? What advice can y'all provide.
Even if the car runs well, for the amount of time and cost involved, I would change them. I have 52K on my 2009 SL550 and I will be changing mine this summer. Like oil, even thought the mileage is low, the oil breaks down and should be changed based on how long it has been in your crankcase. 13 years is along time for corrosion to take it's toll on your plugs.

Nice car!
josephanthony is offline  
Old 05-12-2016, 09:55 AM
  #13  
Senior Member
 
anothercar's Avatar
 
Join Date: Aug 2014
Location: HHI, SC
Posts: 299
Received 20 Likes on 17 Posts
2002 C4 Cab, 2014 Audi A5 cab, 2017 X5 35d
Agreed......although the car runs well it just feels right that a tune-up is in order. Will take it to my indy mechanic soon and post the cost here.
anothercar is offline  
The following users liked this post:
Heatwave (05-12-2016)
Old 05-17-2016, 07:56 AM
  #14  
Member
 
josephanthony's Avatar
 
Join Date: Apr 2012
Location: Hockessin, DE
Posts: 123
Likes: 0
Received 0 Likes on 0 Posts
2009 SL 550 Silver Arrow Launch Edition
Originally Posted by anothercar View Post
Agreed......although the car runs well it just feels right that a tune-up is in order. Will take it to my indy mechanic soon and post the cost here.
You'll be glad you did.
josephanthony is offline  
Old 05-31-2016, 12:54 PM
  #15  
Super Member
 
Join Date: Jul 2010
Posts: 850
Received 95 Likes on 77 Posts
2003 e55, 2003 SL55
the service life is 10 years / 100,000 miles, whichever comes first
carguyshu is offline  
The following users liked this post:
Heatwave (06-01-2016)
Old 02-13-2018, 11:06 PM
  #16  
Junior Member
 
Join Date: Mar 2017
Posts: 17
Likes: 0
Received 0 Likes on 0 Posts
2003 Mercedes SL55
Cool also I used the colder ngk's

Originally Posted by Georgee6086 View Post
Mine had 110000 miles when I replaced them and to be honest they didn't look too bad, the rear ones seemed to have a bit of burnt oil around the threads so I had a leak down test done and everything was within spec. The car did seem to idle a little bit better after the new plugs not much tho, I then reset all the adaptions with star and it smoothed out the idle more. I think the oil is a result of the pcv system pulling oil from valve covers. I will be adding a oil separator soon. Also I used the colder ngk's
How do you determine the colder plug vs. the normal
Woodpecker1 is offline  
Old 02-14-2018, 12:09 AM
  #17  
Senior Member
 
Aussiesuede's Avatar
 
Join Date: Jan 2015
Location: Seattle, WA
Posts: 273
Received 57 Likes on 48 Posts
SL500 (Preparing for SL55 Merge) & CLK430 Cabrio
Aussiesuede is offline  
Old 02-14-2018, 01:40 PM
  #18  
Newbie
 
happypr's Avatar
 
Join Date: Feb 2014
Location: Rochester, NY
Posts: 14
Likes: 0
Received 1 Like on 1 Post
2007 SL550 AMG Sports Package
Thumbs up Do it yourself, save your money !!

I replace my plugs in my 2007 SL550 and it was actually pretty easy !. Just remember 1 plug @ a time. My SL has ignition coils so you don't need a boot removal tool. You'll need a torx to remove ignition coils and a get a torque wrench to torque plugs. I also got NGK Iridium plugs , spend the money you saved on plugs !! Total time was about 1.5 hr. Good Luck !!!
happypr is offline  
Old 02-15-2018, 09:24 PM
  #19  
Member
 
pfarah77's Avatar
 
Join Date: Sep 2015
Location: Plymouth, MA
Posts: 246
Likes: 0
Received 24 Likes on 15 Posts
2008 SL550
I agree with Happypr, just replace one plug at a time and you're all set. Inspecting spark plugs tells a lot about the engine's condition.
pfarah77 is offline  
Old 02-15-2018, 10:54 PM
  #20  
MBworld Guru
 
Rudeney's Avatar
 
Join Date: Dec 2009
Location: Birmingham, AL
Posts: 10,127
Received 765 Likes on 714 Posts
CURRENT: 2011 SL550, 2010 ML350, FORMER: 2007 CLK550 Cabriolet, 2002 C240, 2001 ML320, 1984 300TD
Plugs on the M723 are a much easier job than the M113. For one, the M273 has 8 plugs where the M113 has 16. And then on the M271, they are right there on top, but on the M113, they are on the side of the head and in a tight space - real knuckle busters!
Rudeney is offline  
Old 02-16-2018, 08:17 AM
  #21  
Member
 
pfarah77's Avatar
 
Join Date: Sep 2015
Location: Plymouth, MA
Posts: 246
Likes: 0
Received 24 Likes on 15 Posts
2008 SL550
You know, I heard that just the proper blood to gas/oil mixture makes a car go faster
pfarah77 is offline  
Old 02-21-2018, 12:52 PM
  #22  
Newbie
 
Join Date: May 2016
Location: texas
Posts: 5
Received 0 Likes on 0 Posts
2006 MB SL500
sparkplugs

Changed sparkplugs on my 2006 SL this past weekend, 70,00 miles. I was surprised that the old plugs were NGK-R PFR5R-11. Believe they are the original plugs (they had a “MB star on each plug). I am the second owner and have owned it for over 9 years (40,000 miles). Replaced them with Bosch Double Iridium FD8D1133X (Amazon <$5.00. each). I read some people replaced in 1 to 2 hours. For this 72 year old man it took over 5 hours, but I spent time cleaning each coil and leads and the engine of years of dirt. Cleaned the inside of each booth and applied dielectric grease. Only issue I had was to ensure each lead was tight on sparkplug (some I did not hear the assuring “click”). Installed new air filters while the cover was off.
brutscher is offline  
Old 02-21-2018, 08:40 PM
  #23  
MBworld Guru
 
Rudeney's Avatar
 
Join Date: Dec 2009
Location: Birmingham, AL
Posts: 10,127
Received 765 Likes on 714 Posts
CURRENT: 2011 SL550, 2010 ML350, FORMER: 2007 CLK550 Cabriolet, 2002 C240, 2001 ML320, 1984 300TD
Yeah, changing those 16 plugs on the M113 can be a real chore. With all the extra cleaning, I can see t taking 5 hours.
Rudeney is offline  
 

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 

Thread Tools
Search this Thread
Rate This Thread
Rate This Thread:
You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Changing Spark Plugs 100,000 Miles


Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: