Arifagorilla

Hi

Can anyone here give me a detailed discription on how to change spark plugs on a W211 E320 2003, i had a look at the spark plug placements and man are they in a tough spot. Thank you in advance

Clinton Horn

I was hoping someone would reply. Perhaps not. This would be a difficult thing to photograph. I have a 2003 and one day I will need the same info. I can offer this general help.
1. If you can get a fingernail or dental pick under the edge of the sparkplug boot, gently curl it to break the adhesion from rubber aging. Use a boot puller if you can get to the cap. Pliers are a last resort and will probably damage the boot. I believe a lubricant is available if you plan to try again at 200,000!
2. Don't gap the plugs, platinum / iridium is easily damaged. Unless you drop one, they should be correct.
3. Use a plug socket that has good rubber inside to firmly hold the plug. Obtain 3" 6" and 10" wobble drives and a universal. Determine what will access the worst plug and start there. I have an air socket wrench that has been useful on occasion. When you have the correct set up, tape the connections together. This will insure that the plug socket / extension comes off with the plug intact.
4. HAND START the new plug so that you can feel the threads engage. Using a ratchet to start will increase chances of cross threading.
5. It is likely that some part (s) will need removal. Study which ones will impact your access and remove them until you have a clear shot. A general rule of thumb is that if you can touch the tip of the plug, you can get it in / out.
6. Don't tense up your fist / forearm muscles. This decreases your clearance. You can't muscle your way in, take your time and avoid cramping your fingers.
7. I have conquered some pretty tough situations. Sometimes taking a wheel off to get access through the inner fender helps. You will likely end up sore and bruised but remember, it can be done. If there are any other special tools that are helpful, perhaps someone who has actually accomplished this model will respond.


Good Luck x 12

vettdvr

Take your time.. don't rush. Remember if it is running with old plugs you could change 2 each day and it will still run. It really isn't necessary to complete the job in 1 day. On my corvette I have done 4 on one side. Stopped for 2 days then completed to save the frustration of rushing.

raymond g-

tip....the 17mm open end, offset wrench should fit right into the boot. used as
a fulcrum, it'll pop the boot off w/o damaging.



swivel joints, or flex drive eases the pain immensely

Arifagorilla

Thanks guys, i will try and change them and will let you know how i got on.

bestoverall

It would be nice if you can take some pictures while you are doing the job.

vettdvr

Ok I changed the plugs yesterday on our E500.

I had to use the 17 mm open end to get the wires off the plug. However mine wasn't offset so it was a bit of an issue. I found that prior to just pulling if the plug cap were twisted a bit to break the seal made it easier to remove.

Removing the coils was required to have the room necessary.

The plugs were platnium from auto house ariz. at a very reasonable price. They were the oem plug that matched the plug in the owners manual for the car.

I used the universal and a ratched with flex head. After the plug was broken loose I rotated it about 1/8 turn loose then back tight. Then repeated this. Removal of the plug was very slow and when it got tight I would rotate the plug to tighten to break the carbon loose. All plugs got to where I could remove them by hand. (And are those suckers down in a hole or what). But I got them all out. The new plugs were not gappable and installed as out of the box. I could not get a torque wrench with a low enough range to click at 20 ft #'s. So I tightened them by hand until they would no longer move. Then used the ratched to pull down until it felt solid. The put 20 ft# on it by the clicking elbow method.

All plugs had neverseize on them but a very small amount not goobered up.

I also used a dielectric grease on each plug cap. The amount used was about the size of 1 drop of water and just enough to wipe around the boot. NO EXCESS.

The only down side. The torx for the coil was a 27 not a 25. But I managed to drop my 25 into the engine compartment. I put the car on lift pulled the bottom covers and searched for 2 hrs with a mirror. Finally when I confirmed the torx socket was not on a pulley/belt, starter, gen, ac. or inside the fan shroud I gave up and put it back together. So time for the job. 4 hrs. Time to search 2 hrs. Time to change plugs 2 hrs. But overall it is not a difficult job but you must have a universal or that equivalent and extensions that are mixable to get the correct length.

Would I do it again. Yes,, but the danged sockets etc better not be dropped again.

Davehd2009

Everyone - I am looking at doing a plug change on my '03 E320. After having done this yourselves, would you do it again or shell out the $300+ to have a mechanic do it?? I went through this on my '97 Ford Explorer (V6), and it took 2 days, the removal of a fender well, and some very interesting positions not seen since the kama sutra to get at some of the passenger side plugs - and they aren't buried down inside the engine like on my Merc. All I can say is that I am glad it's only done every 100k miles!!

Davel

i just replaced mine last weekend, i didnt do it but watched the whole process. there really wasnt any issues getting to any of the plugs or removing the plugs or boot/cap that goes over the spark plug. My mechanic use a sort of thong (not the wrench) http://mercedessource.com/node/7952like tool to grab it and then a large screw driver to leverage it off. I was expecting it to be a big deal, took him about 50 minutes and he was putting the plastic engine cover back on. My plugs had
82K miles on them and all looked fine.

Davel

This tool is the only way to remove the spark plug connectors without damaging the wire or boot. If you own a gas engined Mercedes this is a MUST HAVE tool!

Try this link:

http://mercedessource.com/node/7952

Dexion

I posted a DIY on changing spark plugs. Im on my phone for a littlebit otherwise id post the link just search it.

JeffreyP

I just did my spark plugs last weekend, took about 3.5 hours and it's quite straight up work. The two tools above are definitely recommended, you'll also need a 3" extension. Wear thin gloves so you don't get cut and at the same time can feel where the plugs are.

I also recommend a 5/8" non-rubber deep socket to tighten the plugs after initially using the (rubber) spark plug socket to safely screw them in. Reason: the rubber socket tend to stick to the spark plug and hard to get it out after tightening.

The hardest part I found was to reinsert the wires onto the plugs. You can use the 17mm tool above but you have to hear the click and make sure the wires can't be pull out by hand afterward.

Make sure you don't mix up the wires, they are clearly labeled A/B and show which goes on top.

Good luck.

itaven56

Where can I purchase the 17mm offset open end wrench?
I appreciate it.

itaven56

I could not get access to that website.

homeofstone

The off-set tool is also available from amazon.com

vettdvr

I just used a 17MM open end wrench. worked for me. Remember twist the plug before you attempt to pull it off to break the friction.

Long Islander

How many hours labor does the dealer charge for 6-cylinder spark plug change and how much to the parts cost?

cextolauren

It really isn't necessary to complete the job in 1 day

platinumblue

Link below provides same procedure for many of e-class.



Hope this helps.

syedabdulshahid

You can easily change the spark plugs yourself. You need to buy the 17mm offset wrench (tool) to remove the plug wires. For a V6 engine you need 12 spark plugs for a V8 engine you need 16. Just ensure the correct spark plugs for each engine. Do one plug at a time so you do not mess with the firing order of the cylinders.You can get 12 Bosch plugs for $ 60 online with free shipping.The workshop will charge you atleast 4 times the cost plug labor.

Syed E320,190E Ohio