cylinder misfire--spark plug recommendation?
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me: 2015 SL400 & 2015 ML400; wife: 2022 GLC Coupe; daughter: 2017 GLC SUV
cylinder misfire--spark plug recommendation?
(yes, I searched the forum first) I'm getting cylinder misfire codes. CEL will come on, car goes into limp mode, etc. If I shut it off and leave it alone for a while (once was an hour, once overnight) it pretty much resets itself ---CEL stays on, but car runs okay-- but I know if I floor it, it'll limp again. I'm ordering the ignition cables from Fastlane (F1020141213 $205 for set of 12) and want to get plugs, but there's 4 different choices. I've read that the platinums are no good, but does anyone have a recommendation?
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If you do your own maintenance, just stick with some Bosch 7557 Copper plugs. They have to be changed more frequently than platinums but offer better performance. Don't waste your money on Iridiums
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From: Milton/Westport, MA USA
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Steve:
OBS II had every cylinder (except 3) misfiring, and with 70K+ on it, I figure new plugs and wires can't hurt. What could I do to more accurately find the cause of the misfire?
OBS II had every cylinder (except 3) misfiring, and with 70K+ on it, I figure new plugs and wires can't hurt. What could I do to more accurately find the cause of the misfire?
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From: CA
At 70k, I would also change the wires and plugs. My brother's C320 started misfiring @ 75k (bad wires).
BTW, your engine is designed for platinum plugs. The problem is when people start installing them in cars that were never designed for them (M103, M104, M119, etc.).
BTW, your engine is designed for platinum plugs. The problem is when people start installing them in cars that were never designed for them (M103, M104, M119, etc.).
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Originally Posted by eddieo45
Steve:
OBS II had every cylinder (except 3) misfiring, and with 70K+ on it, I figure new plugs and wires can't hurt. What could I do to more accurately find the cause of the misfire?
OBS II had every cylinder (except 3) misfiring, and with 70K+ on it, I figure new plugs and wires can't hurt. What could I do to more accurately find the cause of the misfire?
Think about it...how would spark plugs alone suddenly cause half (I assume you have 6) of your cylinders to suddenly begin losing spark?.Modern ignitions have so much spark energy that they'll fire under atrocious conditions if it's delivered properly and on time.
I suspect the cause of your troubles is further upstream.
As vinamg posted, the best replacement plugs are whatever you car came with.
Last edited by Steve Clark; May 10, 2005 at 03:11 AM. Reason: BR549
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Originally Posted by Steve Clark
I suspect the cause of your troubles is further upstream.
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From: Motor City
95 E320 Cabriolet, 108K
What's the maintenance history of the car?... has anything been done besides fluid changes?... maybe it just needs a regular tuneup.
I agree with replacing the plugs and ign wires. Stay with original-type equipment spark plugs (platinum).
It's a long shot, but if it's misfiring under heavy acceleration, maybe you're getting fuel starvation and the fuel filter needs to be replaced.... just a thought.
I agree with replacing the plugs and ign wires. Stay with original-type equipment spark plugs (platinum).
It's a long shot, but if it's misfiring under heavy acceleration, maybe you're getting fuel starvation and the fuel filter needs to be replaced.... just a thought.
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Thread Starter
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From: Milton/Westport, MA USA
me: 2015 SL400 & 2015 ML400; wife: 2022 GLC Coupe; daughter: 2017 GLC SUV
Originally Posted by Kestas
What's the maintenance history of the car?... has anything been done besides fluid changes?... maybe it just needs a regular tuneup.
I agree with replacing the plugs and ign wires. Stay with original-type equipment spark plugs (platinum).
It's a long shot, but if it's misfiring under heavy acceleration, maybe you're getting fuel starvation and the fuel filter needs to be replaced.... just a thought.
I agree with replacing the plugs and ign wires. Stay with original-type equipment spark plugs (platinum).
It's a long shot, but if it's misfiring under heavy acceleration, maybe you're getting fuel starvation and the fuel filter needs to be replaced.... just a thought.
Also, what would be part of "a regular tuneup"? In the old days, that meant plugs, points, and maybe distributer cap. What's it mean today?
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From: Motor City
95 E320 Cabriolet, 108K
Tuneup for driveability concerns include: plugs, air filter, fuel filter, clean throttle body, ign wires.... not a whole lot nowadays.... and some of these things are only done on an as-needed basis.
Find out what plugs are original equipment and stick with that. I don't know what's original equipment.... my comment on platinum is based on vinamg's comments. And don't assume the correct plugs were put in at the last spark plug change.
Find out what plugs are original equipment and stick with that. I don't know what's original equipment.... my comment on platinum is based on vinamg's comments. And don't assume the correct plugs were put in at the last spark plug change.
