CLA250 Spark Plug Replacement (DIY Definitive Guide)
This is a discussion on CLA250 Spark Plug Replacement (DIY Definitive Guide) within the CLA Modifications / DIY forums, part of the Mercedes-Benz CLA Forum category; Always have though high energy e connections should be dry but then these conductive compounds show up and not only make connect and disconnect easier ...
Always have though high energy e connections should be dry but then these conductive compounds show up and not only make connect and disconnect easier they are supposed to enhance those critical contacts but of course if the compound flows at temp then ... oops
The nonconductive stuff is just to relief the boot friction for easier mount and dismount and seal out moisture ... which makes sense
My compromise would be a tiny tiny tiny smear of conductive on the spark plug contact and a small bit of nonconductive around the boot lip ... get dual benefits
The Deoxit grease is rated up to 250 Celsius (I think that is 550 Fahrenheit) .. that is comparable to the Permatex, and Versachem Dielectrics.
Too late for the Benz ( I am not taking it apart again! ) , but I have a couple of Hyundai Sonatas due (my kids cars) , will try the Deoxit on those.
I thought you were not supposed to put grease on the rubber boot. it would certainly smear all over the plug
I am reading that we are not supposed to get greasy fingerprints on the porcelain part of the plug.
I would be curious to learn more about the OEM dielectric grease, if someone has some, or has some info
on this please post.
I will let you guys know how well my DeoxIt experiment works out.
Re: grease ... yeah two schools of thought
I know dry/dry works and thats a baseline and may just stick with that (... if it aint broke ...)
was watching a timing chain video ... and came across a couple frames which shed some more light on the intake removal thing (well at least according to the germans)
what's left dangling hints at how they prefer to execute the move
Well after trying to datalog my car lots of times, it started runing on 3 cylinders. I thought it was another busted spark plugs but no. I had a "small" issue with a piston. Luckily cylinder wall had zero damage.
Originally Posted by jmc
Finally I fixed it with a new piston and traded it for a C450 AMG. Cant be happier after the hell I lived with the cla.
Guys, don't mess with your ECU. Not worth the risk.
Last edited by chipfuad; 05-29-2019 at 05:52 PM.
You had a ECU Tune or PiggyBack ?
- Campagna T-Rex 2011
- Mercedes CLA 45 AMG 4Matic 2015
Some surface microreliefs must have literally tore up that piston ... or a speck of dirt within the oil spray and caught between the piston and cylinder wall at just the right moment
Doubt anything to do with the tune etc else a lot of us will have busted pistons ... more like contamination in the air and/or oil channels
Hows the new C ?
Also the damage zone is orthogonal to the thrust plane ... if you have pix of that part of the cylinder wall it will be very telling
ECU tune by Brperformance
Originally Posted by David170
These are the best pictures i could find.
Originally Posted by jmc
I really dont know if it was an oil issue or a tune one. I've seen lots of pistons with busted ringlands due to bad tunes (knock) so honestly no big surprise for me although piston crown looks intact and cylinder wall also.
The new C is awesome. V6 twin turbo, 367 HP, 4 matic. Love it!
Great pix to see!
And I stand corrected ... you have a good point cuz a tough ping (bad tune) at the wrong spot in the flame front could do a number on the piston and not on its crown either
So the C is not quite the grandpa mobile ay?