Alex Robbins is contributing editor at Telegraph Cars where, as well as responding to readers’ queries, he also contributes reviews of new and used cars, together with articles on buying and selling. 

His knowledge of the used car market informs his many buying guides relating to the best buys in particular sectors, with an emphasis on value for money.  Every week he will answer your questions on buying and selling, as well as solving your car problems, whether consumer or mechanical.

Do you have a motoring dilemma you’d like our expert to solve?  For consumer and used car advice, or car faults, email CarsAdvice@telegraph.co.uk and include your subscriber number. This week’s question…

Dear Alex,

My daughter bought her first ever (used) car from a Volkswagen dealer with a two-year warranty. After six months, her VW Up is suffering from severe condensation and damp problems but my daughter is being told she has to pay significant costs just for exploratory works. VW Customer Relations won’t deal with it and has suggested the Motor Ombudsman. What do you suggest? 

– SW

Dear SW,

Excessive condensation is usually caused by a leak; once moisture gets into a car, it tends to evaporate then condense on the cold surfaces of the windows and screen. As it happens, Ups can be quite leaky, so condensation is not unusual.

Early Ups had a particular issue whereby the bulkhead seal through which the air conditioning pipework travels from the engine bay into the passenger cabin was incorrectly fitted, allowing water to enter that way. There was a technical bulletin issued on this (though not a recall), so the VW dealer should be aware of it.

I’ve heard of Ups letting in water through the hatchback at the rear, too, although this usually collects in the hatch itself, and you’ll hear it sloshing about when you open the boot. I’ve also heard of the drain holes for the windscreen wiper motor compartment beneath the windscreen becoming blocked, allowing water to pool there and eventually find its way into the passenger compartment. 

Of course, the fault could be none of these things – it could also be a dodgy seal around the doors or hatchback, or even within the engine bay or behind the rear lights. The problem is that most of the likely causes won’t be covered by Volkswagen’s used car warranty because it doesn’t cover damage to the bodywork, which includes the seals, and nor does it cover blocked drainage holes. I should point out for the sake of balance that Volkswagen is not alone in this – it’s a fairly normal clause you’ll find in most used car warranties. 

I reckon the dealer is expecting you to pay for diagnostic work on the basis that the warranty probably won’t cover the fix. Unfortunately, I can’t see a way to convince them otherwise, so I think you’re going to have to stump up for it, and then argue the toss later on if it turns out the problem you’re having was covered after all. 

Furthermore, to try and cut down on the cost, you and your daughter can do some of that diagnostic work yourselves, firstly by checking the interior thoroughly for dampness, particularly in the carpets and spare wheel well. This might give you an idea of where the moisture is coming in.

If it’s in the front footwells, the chances are it’s coming through the bulkhead, either through that seal, or because the scuttle panel drainage holes are blocked, allowing water to pool and enter the ventilation system. 

You can check these drainage holes yourself, by removing the black plastic cover beneath the windscreen – you’ll see the drainage holes beneath the wiper mechanism. If they’re blocked with dead leaves and other detritus, that might be the cause of your problem. 

In the boot, it’s likely coming in through one of the seals around the boot lid, windscreen or rear lights, while if it’s in one of the rear footwells, you’ll want to check the door seals. You can go further by training a hosepipe or pressure washer on the areas where you think water might be coming in and having someone sit inside the car to see if they can spot it.

If you can at least work out where the water is getting in, it might minimise the amount of time the dealer has to spend coming up with a diagnosis, and therefore how much your daughter will have to pay. 

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