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Tips & advice

How to spot a flood-damaged car

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?

The UK receives a not-insignificant amount of rain and our roads can often struggle to cope with very heavy downpours. The result can be waterlogged sections of road and, inevitably, many cars end up getting  flooded as a result. A flood damaged car means big trouble for the owner and potentially, also for any unsuspecting buyer who might be looking at purchasing the vehicle at some point in the future.

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Here we examine ways to mitigate the effects of water damage to a car and of spotting flood damaged cars being offered for sale.  Whether your car is parked at the roadside or you’re wading through waterlogged sections, there’s always a chance that your car could become flooded. The best advice is to try and avoid the worst coming to the worst in the first place by choosing your parking space carefully when wet weather is expected and never driving into water if you’re not completely confident that you can make it out the other side.

What are the effects of flooding on a car? 

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 from city cars to 4x4s, water damage could affect mechanical components like the engine, brakes, starter motors and catalytic converters, not to mention the electrical system. 

Any kind of flooding could spell serious issues with the car for years to come and it’s not surprising that some unscrupulous motorists attempt to sell flood damaged cars without being completely honest about their watery history.

How to check for flood damage on a car

Selling a flooded car that’s not had critical components replaced or repaired could be like selling a ticking time bomb of expensive and even dangerous problems. Below are a few symptoms to look out for and easy checks to make if you suspect you’ve got a flood-damaged car on your hands...

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  • 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.

What to do if you suspect a car has been flood damaged

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 S and Cat N (or Cat D and Cat C under the old system) 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. The asking price could look tempting and previously written-off car could represent a bargain, there’s even scope to use a flooded car for parts - 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 occurred. As always, if you're not absolutely confident in the car's condition, walk away.

Buy a car with Auto Express. Our nationwide dealer network has some fantastic cars on offer right now with new, used and leasing deals to choose from...

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