Spark Plug Issue
#1
Senior Member
Thread Starter
Spark Plug Issue
So the other week I installed new spark plugs. They were Bosch YR7MPP33, I check multiple places and I was told I needed Bosch YR7MPP33. After I installed them my engine started stuttering/knocking. I checked my old spark plugs and they are Bosch Y7MPP33.
What is the difference between the two? What spark plugs are y'all running in your 08 c300?
What is the difference between the two? What spark plugs are y'all running in your 08 c300?
Last edited by W204Man; 03-19-2015 at 01:19 PM.
#2
Member
MB specs call for the Y7MPP33 (without the "R") but it should not make a difference IMO. The "R" in YR7MPP33 stands for "resistor", which Bosch says is installed to eliminate interference with electronics like AM radio signals.
Are you sure all your coil packs are installed back correctly and none were damaged?
I just found this thread that has some interesting info on YR7MPP33 vs Y7MPP33 spark plugs in MB engines.
http://www.peachparts.com/shopforum/...sch-plugs.html
Are you sure all your coil packs are installed back correctly and none were damaged?
I just found this thread that has some interesting info on YR7MPP33 vs Y7MPP33 spark plugs in MB engines.
http://www.peachparts.com/shopforum/...sch-plugs.html
Last edited by Antique-Ace; 03-19-2015 at 01:46 PM. Reason: Added additional info.
#3
Senior Member
2009 C300.
Had the spark plugs replaced by local indie shop owned by an MB master mechanic. The invoice has YR 7 MPP33 as part number.
Had the spark plugs replaced by local indie shop owned by an MB master mechanic. The invoice has YR 7 MPP33 as part number.
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2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
From personal experience, Mercedes factory plugs can be either Bosch or NGK. Had 2 cars with M112 engines. One had Bosch from the factory and the other, to my surprise, had NGK. Some engines, like the early M276, where spark plugs were developed specifically for that application with the vendor, will have only one brand available until the design is released to the aftermarket.