-Spark plugs--quick advice
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From: Clearwater Beach, Florida
2016 Cls63s AMG
-Spark plugs--quick advice
hey fellers what would be some good spark plugs for our w124's? last time i bought some expenisve ones and the guy at shucks said that they were not good even tho they were expenisve so i went ahead and bought them anyways but i think they kinda hesitate when my car trys to start?
what shall i get?
what shall i get?
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From: Orland Park, Illinois
1994 E320 (current)
hey fellers what would be some good spark plugs for our w124's? last time i bought some expenisve ones and the guy at shucks said that they were not good even tho they were expenisve so i went ahead and bought them anyways but i think they kinda hesitate when my car trys to start?
what shall i get?
what shall i get?
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W124, W220 S500 4matic, W140 S500, CLS55 AMG
I would stick with the original Bosch h9dc0 plugs for the m103 engine. If I were you I would call your local MB dealer and stock up on these as they have stopped making them from what I understand.
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
I use NGK BP6EFS in my M103-12V twin turbo.
Manufactured in France, so should be available in your area.
The "R" in the HR8DC stands for "resistor", which you don't want to use.
Resistance is built into the cable end on the M103-12V.
Ed A.
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W124, W220 S500 4matic, W140 S500, CLS55 AMG
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From: Clearwater Beach, Florida
2016 Cls63s AMG
i just put some nkgs yesterday.... and they seem to be great, my car used to shake a bit but now its all nice and quiet and you cant even tell its on...
i changed my cap and router a month or two back too soo it was a nice little tune up..
i changed my cap and router a month or two back too soo it was a nice little tune up..
Last edited by berti_00; May 8, 2008 at 11:27 AM.
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From: Mojave Desert, Ca.
1990 300CE
Info NEEDS to be correct, not guesswork.
Resistance does NOT ruduce the spark at the plug!
Resistance is in the wires and plugs to reduce the "electical noise" that would be otherwise sent thoughtout the cars electrical systems. The radoi would let you "hear" that noise through the speakers. This is very annoying for the driver.
Also without that resistance the computer systems could act up and cause other problems.
The only way a sparkplug wire can harm the cap or rotor is when the spark has no place to go but inside the cap, like when someone pulls off the wire at the sparkplug to test if that cylinder is working.
All of this info is TAUGHT at any automotive training school. You can also find it throught the web at places like Auto101.
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From: Clearwater Beach, Florida
2016 Cls63s AMG
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W124, W220 S500 4matic, W140 S500, CLS55 AMG
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From: Orland Park, Illinois
1994 E320 (current)
Thread Starter
MBWorld Fanatic!
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From: Clearwater Beach, Florida
2016 Cls63s AMG
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From: Mojave Desert, Ca.
1990 300CE
Also, as I have modified my Supra (Toyota sports car), And lots of other cars, I have a pretty good working knowledge about ignition systems.
My opinion about modding these W124's is: if you don't have lots of $$$ to throw into it (like having an expert do a lot of work), or you need to drive it every day, and.... if its running good with factory parts, or aftermarket "equivalent" parts, then leave it alone.
Just doing things like spark plugs and wires and minor things is NOT going to give you a noticable HP gain. But, it could cause drivabilty troubles, which WILL drive you crazy.
Last edited by mr300ce; May 11, 2008 at 11:20 PM.
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From: Orland Park, Illinois
1994 E320 (current)
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From: Harpenden, Hertfordshire, England
1996 W124 E320 Coupé, 1990 W124 300E twin turbo, 1991 W126 300 SE, 1984 Ford Capri 2.8i
Beru 14K-8DU, 14K-8DUO
Bosch H8DC, H8DCO
Champion S10YCC
But, the table is headed with "Basic and national versions (except Australia, Japan, USA, Korea, Taiwan)". What the differences are there is not revealed.
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From: Mojave Desert, Ca.
1990 300CE
Even a "Little" Bad Info Can Screw You Up
The MB Technical data passenger cars reference manual (October 1993) confirms 8mm as the electrode gap on all the engines it covers: 102, 103, 104, 111, 116/117, 119, 120. It shows the following for the M103:
Beru 14K-8DU, 14K-8DUO
Bosch H8DC, H8DCO
Champion S10YCC
But, the table is headed with "Basic and national versions (except Australia, Japan, USA, Korea, Taiwan)". What the differences are there is not revealed.
Beru 14K-8DU, 14K-8DUO
Bosch H8DC, H8DCO
Champion S10YCC
But, the table is headed with "Basic and national versions (except Australia, Japan, USA, Korea, Taiwan)". What the differences are there is not revealed.
S/B 0.8mm = 0.32"
Hey fellas, lets ALL be more precise when giving info & advice here, because the the guys trying to learn how to DIY could really do some damage to their car following erroneous advice.
The BEST advice I can give is for each & every one of the members to purchase Haynes or Chilton manual for their model.
I've never been a fan of these brands, as they are lacking info for the working tech, so I always get the factory manuals too.
But there is enough info in them for the DIY'r, like the sparkplug gap, and how to set it.
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1999 E320
Dude, you are so right about these. My car has had the typical '80s Mercedes misfire, but since the previous owner had just done a tune-up I decided to leave the plugs alone since I didn't think they could be the cause after me only putting 1k miles on the car since I bought it.
Well, without even pulling the plugs out first to check (haven't had time), I ordered some H8DCs so that I would have them when I got around to checking, just in case.
FedEx just showed up with the new plugs, and I'm not working today so I got out my 5/8" spark plug socket and my torque wrench, and whaddya know? HR9DCs. Now, at this point I still didn't know whether these plugs were just a hotter version of the H8DCs (the plugs looked completely normal -- no fouling, cleanly burned, etc.), but I swapped them out anyway.
The car now runs better than the day I got it, and the misfire is gone completely.
The car was running so poorly last night that I even bought a new direct-fit catalytic converter off eBay (a typo listed it with a BIN of $25 with free shipping, so we'll see if they actually send it or just refund my $$) so that I would have that on tap, as well as a new ignition coil (all of this is still cheaper than sending the car off to a shop, plus i know exactly what is going into the car).
Cliff's notes:
F*ck HR9DC plugs.
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From: Long Beach, Ca
lots of cars
You can run h7dc if you can find them...but yeah h9 h8 h7 are just different heat ranges and the R means resistor. H8 was too cold of a plug for the age of the engine. H9dc and 91 octane makes my car run really smooth. It would help if you ran a bottle of fuel system cleaner and change the fuel filter. When I got my car back in 2001 I did a complete tune up and even changed most of my steering parts and suspension because i couldn't trust the previous work done to the car. I would look at fuel system and if the fuel filter still looks original i would replace it. I would also get the injectors checked and replace the rubber seals if they are hard.
