At what point does a car become unfit for purpose?

I'm having lots of software problems with my Volvo XC90. Many of the functions for which I bought this car don't work at all, or work for a while after a software update and then fail again. My dealer is sympathetic but appears to have little regular support from Volvo.

I have also had issues with excessive road/suspension noise. I've gone as far as replacing the original 21-inch wheels on my car with 19-inch wheels but it's made very little, if any, difference. Again, dealers are sympathetic but have no solution.

Volvo may well say that tyre noise, even in a car in the "luxury" bracket, is subjective but they can't contest the fact that our software/electrics are incomplete and unreliable. Do we have a case to return our cars on the grounds that they are not fit for purpose?

Asked on 8 July 2016 by Batchem1

Answered by Honest John
Tyre noise is not subjective. It can be measured and indeed is measured for EC tyre labelling. But you can lower it by lowering the tyre pressures. Manufacturer recommended pressures are usually too high and result in harsh ride and high noise. I'd be looking at trying cold pressures of around 32psi all round. These raise by about 2psi as soon as the car is driven and can rise as much as 5psi on a long motorway run in high ambient temperatures. So if the cold pressures are 36psi all round, you could be running at 40-41psi after 50 miles. As for the software problems, we didn't have any when testing the D5 and the hybrid, but had to switch off the intrusive self-steering function that simply didn't work consistently anyway.
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