How to spot a flood-damaged car

20 Jan, 2016 8:00am Tom Wiltshire

Are you buying a car that’s been damaged by flood water? Read our guide to learn how to sidestep a damp squib

Flood water can have a huge effect on a car, both seen and unseen. But how do you know if the car you're about to buy is flood-damaged?

December 2015 was the wettest on record in the UK, and the country definitely felt it. Floods were widespread and with that came roads under feet of water. Inevitably many cars were flooded, while either parked at the roadside or attempting to drive through waterlogged sections. Now some of those cars will be for sale on the used car market giving prospective buyers something else to look out for. 

• All about insurance write-offs

Lots of people innocently assume that once a car’s been flooded, all it needs is a good airing-out and plenty of time to dry off. What they don’t realise is that water damage could affect engine components like the brakes, starter motors and catalytic converters, not to mention the electrical system. Selling a flooded car that’s not had critical components replaced could be like selling a ticking time bomb of expensive and even dangerous problems.

There are a few key ways to check if you’ve got a flood-damaged car on your hands and you'll find them below...

  • • Do a vehicle check: Some unscrupulous types will buy a car that’s been written off with flood damage and re-sell it without telling buyers the history of the car. An HPI check tells you if the car has been previously written off.
  • • Check the electrics: If the car’s been flooded, it’s likely the electric system has suffered. Check all lights as well as items like the electric windows to ensure they work.
  • • Look for damp: Some areas of a car are difficult to dry completely, so check in the footwells to see that the carpet is dry. Damp carpets are a warning sign that the car may have been flooded and so is that telltale damp smell.
  • • Check for rust: Plenty of used cars will have minor rust, but check that it’s consistent with the age and mileage of the car. Excess rust or corrosion could signal that the car’s been water damaged in the past.
  • • Look under the bonnet: Make sure there isn’t excessive rust or corrosion under the bonnet, and check for water. If in doubt, bring a mechanic along who can check crucial parts like the starter motor.
  • • Put the heating on: Trapped water in the heating and ventilation system could lead to excess condensation – try putting the heating on and see if the windows start steaming up.

If it turns out that the car has been flood-damaged, you should have proof provided that necessary work has been carried out. Ensure the car’s been checked over by a mechanic and is safe to go back on the road. 

If the car has been written off, be aware that Cat D and Cat C write-offs may be made roadworthy again. You shouldn’t pay market value for these cars, however, so negotiate a good deal. If the car is a Cat B or Cat A write-off, just walk away – these cars can never be made roadworthy by law.

As with any used car purchase, it's important to keep cool and be savvy. A previously written-off car could represent a bargain - but a flood-damaged car could also be an expensive mistake. We would always proceed with extreme caution if you suspect a car is flood-damaged and be particularly wary of cars advertised at mysteriously low prices in areas where flooding has occured. As always, if you're not absoloutely confident in the car's condition, walk away.

Would you consider buying an insurance write off? Let us know in the comments...

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