Car won't start after driving through flood water - what could the problem be?

I recently drove my BMW 1 Series through a flooded ford. The car now doesn't want to start and I get a *click* noise when I press the start button. Any idea what could be wrong?

Asked on 3 January 2020 by Tim

Answered by Honest John
If water got into the combustion chambers then the engine is probably suffering from 'hydraulic lock' where the pushrods are bent because the pistons cannot compress the water in the combustion chambers. If you are lucky the fault is nothing more than swamped electrics. The 'click' is the relay between the battery and the starter motor opening because tbe battery cannot turn the starter motor.
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