I am about ready for a tune up and have always put in the non resistor OE Bosch plug. I have read all about not putting in resistor plugs yet I have always had great luck with the NGK plugs in other cars. I got an email from a CS rep at NGK telling me that it should not be a problem putting in the appropriate NGK resistor plug in my SL500.

What's the latest in this long running debate. This is a 5.0 liter V8. What's the consenus these days.

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Wilmington, NC

1996 SL500 Mine!!!
2010 Hyundai Genesis 4.6 with Tech Pkg(Wife's)

Put Bosch in your Mercedes!

Save the NGK's for your Lexus

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MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator

Don't a host of recent Mercedes come OEM-fitted with NGK sparkies?

I replaced my Bosch F8DC4 (non-resistor) with NGK BCP5ES (non-resistor), and it seems fine. I've ran NGK's on everything I've owned, so this was a no brainer.

Next time, I'll try using resistor plugs, in case the extra 5K Ohm gives less electrical noise at higher RPM.

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Beware of stealers
(and shill posters who work for stealers)

Bosch or NGK are both fine. Some are suggesting that Bosch quality is suffering and that Bosch non-resistor plugs are now rare.

If you need non-resistor plugs, Beru ones are easy to find (well, in Europe anyway) and are of excellent quality.

My 1991 300CE was transformed when I removed €100-worth of MB-supplied resistor plugs and installed €20-worth of Beru non-resistor plugs.

RayH

I use resistor NKGs with non resitor wires. No problems. People are making a mountain out of this whole resistor/no resistor thing. If you put any NGK next to a bosch you'll see the build quality is much better on the NKG.

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CENSORED due to not family friendly words