We bought a faulty car from 130 miles away - do we have to take it back to this dealer for repairs?

We bought a 2008 Vauxhall Zafira, 55,000 miles, for £2495 on 22 July 2017 and drove the 130 miles home with no issues. On the 23 July the exhaust emissions light came on, so I contacted the seller and said we would take it back as soon as we were able to. A few days later, the car developed a clunking noise on the passenger side. I contacted the seller again about this and they've said we can take the car back for repair on 3 August as this is the soonest we will have time to take the car in. I'd like to know if the car is safe to drive and who's responsibility would it be to get the car there? Also, in the three month warranty it states that if the vehicle is dealt with by another garage then it invalidates it. Where do we stand on this or are we able to reject the car as it's not satisfactory or fit for purpose?
Law here: www.honestjohn.co.uk/faq/consumer-rights/ The dealer is responsible for any faults that could have been present or developing on the car on date of sale for six months from date of sale. The three month warranty is irrelevant. But you do have to take it back to him for repair.
Answered by Honest John on

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