I recently replaced the lower wiring harness on my coupe, and while I had everything apart I noticed the starter looked original. Since on a few occasions over the course of a year I had gotten a "click" on a very hot start, and the car was 16 years/130K old, I decided to change the starter as well. I was very pleased to find a much faster cranking speed which has completely gotten rid of the long crank/2nd try start that was sometimes very irritating. I've always thought that either a starter turns or doesn't, but never considered that an old starter might turn slowly enough to cause hard starting problems.

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1983 380SL
1995 C280
1995 S500 coupe
1990 Mazda Miata
2004 Suzuki Hayabusa