I own an X Reg Subaru Impreza Sti version 6 JDM. This summer there was a minor but irreparable leak in the radiator. There was steam but there was no apparent overheating or smoke. I had the car towed to a garage who fitted a new radiator after some difficulty identifying and locating a suitable part. I was informed that all appropriate tests had been carried out and that the problem was fixed.

The car ran smoothly for the next month. I did two journeys of about 480 miles as well as a couple of small ones. I then suffered a major problem with the new radiator. I had just pulled off a motorway when the car stalled. I thought that there might be a problem when I restarted it (the check engine light came on) and immediately pulled over. The radiator was in the final stages of dumping all of its water through a 5-10mm hole. The hole was on the back of the radiator, towards the drivers side and about ¾ of the way down. It was inside a protruding ring on the radiator (not sure what it was) and felt jagged.

A nearby service centre confirmed that the head gasket was gone and so I had it towed to the garage that had fitted the new radiator hoping that either the warranty or sales of goods act might come to my rescue.

When they inspected it they said that it could not have been caused by stone chip damage due to the position of the hole. However, they did say that it looked odd, and although they would ‘see what they could do with their supplier’ they thought it might not come to anything.

For good measure they said that in any case the damage to the radiator might have been caused by an underlying problem. The garage sent some photos, and then the radiator itself, to their supplier. The supplier said that it looked like the radiator had been tampered with and thus they were not liable for any damage caused (but would supply a new radiator free of charge as a gesture of goodwill). The garage apologised, said that there was nothing further that they could do and quoted me a price for the engine repair (upwards of £1500+VAT)

Can you give me any advice as to whether the garage and/or supplier is in any way liable for this damage and what the likely cause of it was? There is no possibility that the car had been tampered with as it is kept in a guarded armed forces base and in any event had made the first 100 miles of the journey with no problems.