2015 GLK350 Alternate Spark Plugs
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2015 GLK350
2015 GLK350 Alternate Spark Plugs
Please redirect me to other thread if this one is redundant.
I am about to perform first Spark Plug change on my 2015 GLK350 (276 Engine), and purchased OEM MB Plugs from the dealer, as well as BOSCHZR6SII3320 [OE Fine Wire Double Iridium; Pre-Set Gap: 0.027" (0.7mm)] from RockAuto.
The gap, and the overall electrode geometry look very different between the two sets of plugs, and although I understand the Bosch are Double Iridium type, I wondered if anyone here had any experience with these alternate to OEM Spark Plugs?
I am also replacing the coils with BOSCH branded coils (Coil 5 of the factory installed coils has failed).
Thank you
I am about to perform first Spark Plug change on my 2015 GLK350 (276 Engine), and purchased OEM MB Plugs from the dealer, as well as BOSCHZR6SII3320 [OE Fine Wire Double Iridium; Pre-Set Gap: 0.027" (0.7mm)] from RockAuto.
The gap, and the overall electrode geometry look very different between the two sets of plugs, and although I understand the Bosch are Double Iridium type, I wondered if anyone here had any experience with these alternate to OEM Spark Plugs?
I am also replacing the coils with BOSCH branded coils (Coil 5 of the factory installed coils has failed).
Thank you
Last edited by CERNICALO1; Sep 27, 2022 at 09:24 AM. Reason: incorrect year listed on Title
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
They shouldn’t look different. They’re identical.
The part OE number is
https://www.mbpartshaus.com/oem-part...Y2LWdhcw%3D%3D
Tap the picture to enlarge.
The part OE number is
https://www.mbpartshaus.com/oem-part...Y2LWdhcw%3D%3D
Tap the picture to enlarge.
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2013 glk 350
Why do you have two sets? They are not cheap, what are you going to do with the second set? Gap should be the same and factory set, measure the gap and use the correct ones which will probably be the ones from MB , contact the plug manufacturer. Maybe one set is your famous Chinese bs.
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2015 GLK350
Thank you
Thanks for the replies. You were correct the MB and the BOSH plugs were exactly the same, there was some "smoke in the cockpit" at home.
BTW, I bough the 6 plugs at the dealer, for reference, while I was there for other items. Ended up installing the BOSH plugs, but I am having issues starting the car after also changing ignition coils, and PCV Valve (which also requires the High Pressure Fuel Pump to be partially removed)
BTW, I bough the 6 plugs at the dealer, for reference, while I was there for other items. Ended up installing the BOSH plugs, but I am having issues starting the car after also changing ignition coils, and PCV Valve (which also requires the High Pressure Fuel Pump to be partially removed)
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
IMHO, this engine should have had “forever” spark plugs but the 2015 service manual recommended 46,500 mile replacement. Why was this needed with double iridium plugs?
The WIS procedure involves removing the intake manifold. Reinstalling it needs new gaskets and careful reassembly to avoid air leaks.
The “shade tree” method doesn’t remove the intake which eliminates the leak problem. But access is tight and it makes reinstalling the coils and seating the boots more difficult. Most DIYers use this method, but dielectric grease or silicone lube is needed to seat the boots.
Which method did you use?
Replacing the crankcase vent valve on my 2015 did not create any starting issues.
The WIS procedure involves removing the intake manifold. Reinstalling it needs new gaskets and careful reassembly to avoid air leaks.
The “shade tree” method doesn’t remove the intake which eliminates the leak problem. But access is tight and it makes reinstalling the coils and seating the boots more difficult. Most DIYers use this method, but dielectric grease or silicone lube is needed to seat the boots.
Which method did you use?
Replacing the crankcase vent valve on my 2015 did not create any starting issues.
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2015 GLK350
Further Questions - Help Needed if Possible
Thanks for your replies.
I did take the manifold off, and replaced the 6 intake plenum/manifold gaskets prior to reinstall (holes kept well covered during repair). I did not use dielectric grease for the plugs, but made sure to push in the new ignition coil boots into the plugs as I replaced both.
My fear is that the follower between the camshaft and the HPFuel Pump may not be sitting in place correctly after I reassembled that area. Secondarily, perhaps the plugs and the coil buts are not making perfect contact.
However, I am hoping that I am missing a much simpler step to either re-set a fuel cut off switch (I just disconnected fuel lines from HPFP, w/o any prep step for fuel pressure drop), or perhaps a step required to remove any air from the engine section of the fuel lines. Do you know of any such procedures?
Thanks again for your help!
I did take the manifold off, and replaced the 6 intake plenum/manifold gaskets prior to reinstall (holes kept well covered during repair). I did not use dielectric grease for the plugs, but made sure to push in the new ignition coil boots into the plugs as I replaced both.
My fear is that the follower between the camshaft and the HPFuel Pump may not be sitting in place correctly after I reassembled that area. Secondarily, perhaps the plugs and the coil buts are not making perfect contact.
However, I am hoping that I am missing a much simpler step to either re-set a fuel cut off switch (I just disconnected fuel lines from HPFP, w/o any prep step for fuel pressure drop), or perhaps a step required to remove any air from the engine section of the fuel lines. Do you know of any such procedures?
Thanks again for your help!
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
A quick check would be the fuse for the fuel pump control unit. On my W204 it's fuse 34, maybe the same on the X204 but I don't have my GLK any more to check. I don't think there is a fuel pump cutoff switch that can be reset. The collision function is handled by the pyrofuse on the pre-fuse block, but nothing would work if that was blown.
Beyond that one quick fuse check, I would suggest scanning for codes to help locate the root of the problem. It is highly unlikely that you would have poor connection on all of your spark plugs anyway.
Beyond that one quick fuse check, I would suggest scanning for codes to help locate the root of the problem. It is highly unlikely that you would have poor connection on all of your spark plugs anyway.
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2015 GLK350
Job Complete - Thank you all
Thanks guys for the information. I just finished and the car is running pretty well.
The issue turned out to be that the cam follower for the HPFP had actually completely fallen off at some point while I was working on the PCV (I was exhausted, and missed it). The sucker actually hid from me when I went looking for it once the car did not start, but when I confirmed it was not it place, I had to get a mechanic's mirror with lights, and spotted it in a nook on the back side of the engine.
I am confident that I can perform the PCV Valve, plugs, and coils replacement now in less than 2 hours, but man...., what a pain in the *** the first time.
Best of luck to you all
The issue turned out to be that the cam follower for the HPFP had actually completely fallen off at some point while I was working on the PCV (I was exhausted, and missed it). The sucker actually hid from me when I went looking for it once the car did not start, but when I confirmed it was not it place, I had to get a mechanic's mirror with lights, and spotted it in a nook on the back side of the engine.
I am confident that I can perform the PCV Valve, plugs, and coils replacement now in less than 2 hours, but man...., what a pain in the *** the first time.
Best of luck to you all
