Mercedes c300 2013 110k miles randomly misfiring throughout multiple cylinders
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2013 C300
Mercedes c300 2013 110k miles randomly misfiring throughout multiple cylinders
I have Mercedes c300 2013 that has had multiple misfires and a rough idle the first misfire was in cylinder 1 so i change all the spark plugs it fixed it for about a day then i got a misfire in cylinder 5 so then i order a pcv valve and replaced it and it didnt fix it but the next day i ran sea foam spray for carbon cleaning and injector cleaner (the injector cleaner was in it since the change of spark plugs) but once i put the sea foam in it, it didnt have a misfire until 2 days later in cylinder 1, 2, 3, and 4 so i thought to put sea foam back in it again to see if it would fix it and sure enough it did, most the time the idle would be really rough from im assuming the misfires and thats when it would start was at the idle so after putting carbon clean in it and driving it for about 20-30 mins and letting it idle for 5+ mins i wasnt getting any codes, but 4 hours later i go and drive it and the misfire is back any ideas of what is wrong my next guess is the injectors are getting clogged. i have the m276 NA engine / 3.5L V6
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Joined: Aug 2023
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From: MA Coast
W204 2010 C300 4matic Sport M272
Are you saying there are no codes? or are there codes, and what are they?
Where are you putting the sea foam? Ill put a bottle in the gas tank once in awhile when im thinking the engine idle is a little rough at stop lights. But i never used it to fix misfires.
Where are you putting the sea foam? Ill put a bottle in the gas tank once in awhile when im thinking the engine idle is a little rough at stop lights. But i never used it to fix misfires.
