BrianE

Changed out my spark plugs with Bosch Double Platinum on my 2010 E350 last week and have noticed that my gas mileage has gone down about 2 mpg. I've read on other forums that the Denso Iridium Power spark plug gets better mileage due to a hotter spark which burns fuel more completely. Is this the case? Anyone have any luck with these spark plugs? If so, what's the part number?

Thanks

GuestFromTampa

I used NGK Laser Platinum Spark Plug (PLKR7A) purchased in Advance auto parts http://shop.advanceautoparts.com/p/n...rm=spark+plugs
- great spark plugs, definitely increase in gas milage

homeofstone

+1

Chris_tA_4

What gap did you guys set the spark plugs to?

samaritrey

Shouldn't have to adjust them and most modern plugs shouldn't be messed with if they are not set properly then get an exchange.

GuestFromTampa

NGK Laser Platinum Spark Plug (PLKR7A) are already gapped.

cocobeex

How about this one ?

NGK Iridium IX® Spark Plugs
http://www.ngksparkplugs.ca/products...-iridiumix.cfm

Arrie

I also have only good experience with NGK spark plugs.


Anyone know if this same one works with the 5.5 L engine?


What is the tightening torque for them?

GuestFromTampa

i do i have E550
Tightening Torque: 23 Nm

Arrie

So you have the older true 5.5 L engine and not the newer 4.7 L, right?


Thanks!!

GuestFromTampa

right NA 5.5 engine

BrianE

Thanks! I'll give those a try

C230Brit

At what time / mileage should you change the sparks?
I appreciate there are other factors too, such as driving conditions, etc - but just curious what the general 'accepted' timing is.
I guess the question could be; what is the shelf life of the OE sparks?

thefisch

I think for the 2010-11 V8 the maintenance guide says to change the plugs every 6 years or 60k miles.

Arrie

Just checked it today. The service manual in my 2010 E550 says to change the spark plugs at 120000 miles. Not before that.

C230Brit

Thats quite some time - I'm not even sure I would own the same car that duration / milage - my commute is less than 10 miles

I assume there is no harm in changing the plugs earlier, aside from not changing the spark plugs correctly, etc.

Anyway, thanks for the feedback and useful to know what brand(s) people are using too.

thefisch

Wonder if they changed it. I based my response on the online maintenance manuals that I looked at back when I was researching 2010 and 2011 models. The one they have online currently for 2010 models says to replace every 6/60. See pages 35 and 87 of this manual. http://www.mbusa.com/vcm/MB/DigitalA...ce-Booklet.pdf

It actually applies to both the V6 and V8 engines except the diesel for that year. Guide is the same for 2011 from what I can tell.

Arrie

No, they did not change it. I took a closer look and sure enough it says on the last row of the required service (after all "visually inspect") to change the plugs at 60 000 miles. Interestingly, when I go thru all of my service records the plugs were never changed and I have over 90 000 miles on the clock now. And all service has been done at MB dealer. I need to have a word with them...


Thanks for the heads up!


Edit: In my case it is not the end of the world as 90 000 miles in my car means probably only 40 000 miles worth of average engine time as about 85% of my driving is on highways but still, my dealer service should have asked about changing the plugs.


I will probably do it myself now as it should be quite easy job to do and I do like working on cars.

Arrie

What plugs did you have before? The NGK PLKR7A is listed as the spark plug in the owner's manual for my car.


This is a big surprise as I could have sworn it to be BOSCH but NGK it is.

GuestFromTampa

I think I've had original factory spark plugs , each spark plug had Mercedes logo printed on it. Dont know if it was a BOSCH or an NGK

Arrie

Plugs had MB logo on them??? Never heard of that before. Are you just giving us a "story"? If so stop posting.


Anybody else had MB logo spark plugs on their car???


I changed my plugs today. What came out from the car as the original plugs were the NGK plugs. The same went in to replace them.


In 90 000 miles the gap in the plugs had worn to about 0.0032-0.0033 while the new ones were at 0.0031. I have not done driving yet to tell if this made a difference in anything but I should know soon.

GuestFromTampa

Yeah , you got me . I have nothing else to do so I am giving you " a story " ...

Arrie

Ok,


I believe you now. I have never seen or heard of a spark plug with the car maker's logo on it. Now I have.

GuestFromTampa

I am glad i earned your trust now ! I can see that you obviously know alot about cars ) unfortunately it does not prevent you from suspecting the others is that they come up with "stories" and to tell them to stop posting.

thefisch

Arrie, any comments on cost for the new plugs and the replacement procedure? Was it straightforward?