Strange ignition fault.

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ah
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Post Wed Oct 08, 2014 9:08 pm

When I start my car, sometimes it turns over at what say normal stater motor speed and the next time it turns over slightly slower but it starts on both occasions.It has a brand new battery about six months ago and a brand new stater three months ago,any ideas,could this be the start of a larger problem.
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Born on the 23 April 1990 320i Alpinweiss ll kabriolett! (SOLD BUT NOT FORGOTTEN !) :cry:
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Brianmoooore
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Post Wed Oct 08, 2014 10:12 pm

After it cranks slowly, touch both battery connections, the other end of both battery leads (one is on the starter motor), and both ends of the engine to body earth strap, to see if any of them are hot. If any are, take that joint apart and remake it.
A starter motor usually consists of effectively two motors in the same case, each with its own pair of carbon brushes. If any of these brushes gets stuck and doesn't make proper contact to the commutator, the motor will only develop half power.