Driving through deep flood water - what is safe depth?

I've just spent six hours driving a motorway route (A55), which normally takes two. The motorway was closed by the Police due to floods, and we were diverted onto the A470 to Betws-y-Coed and A5 to Bangor.

The A5 was also flooded with DEEP water in a number of places. Cars were getting flooded and stuck! What is the safe depth of flood water for me to drive through without damaging my diesel Volkswagen Passat estate?

Asked on 23 November 2012 by Ian R. Lee

Answered by Honest John
Check where the air inlet for the engine is, by which I mean the air for the injection system. If any water gets into the engine via that, then the pistons cannot compress it and your engine will be wrecked.
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