The experience of several people I've been in contact with is that they last about 35-40 thousand miles. Mine were all replaced at 35K and again at 76K. The only indication both times was the miss upon startup. The indicator light and the dash info panel never said anything was wrong. The miss cleared up and the engine ran fine once the offending cylinder got hot enough to fire on its own.

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Rick Miley
2014 Tesla Model S
2018 Tesla Model 3
2017 Nissan LEAF
Former MB: 99 E300, 86 190E 2.3, 87 300E, 80 240D, 82 204D Euro
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