I know a little about cars. A lifelong hobby!
This would probably be an oil water intercooler (as opposed to what is normally called an intercooler which doesnt carry oil and cools induction air. )
Whether a leak is serious or not depends on where it’s coming from and how quickly it’s leaking. Certainly, a leak from an oil filter is serious and that should have been resolved.
I cannot accept that they told you that they had given you the car back with an oil leak.
If you lost all your oil whilst driving, and surprised that your car is wrecked and needing a new engine.
The legal situation is that they are in breach of the provisions of the Consumer Rights Act because they have failed to carry out the job with reasonable care and skill and as a result of that you have suffered loss.
There is also the common law negligence issue where for there to be a claim there needs to be:
1. a duty of care
2. the duty needs to be breached
3. as a result of the breach there needs to be loss injury or damage
4. the loss injury or damage must be as a result of the breach
5. it must be reasonably foreseeable.
In your case I think that all of those are satisfied. Claims will often fall down on 5 but in your case, I think that it’s reasonably foreseeable that if a car is “repaired” incorrectly and there is an oil leak, that it would break down.
The thing is of course that you can’t beat the garage with a stick until they pay up and if they want to pay up, your only remedy is to take them to the Small Claims Court.
If you had missed your connection or ferry or at to pay a couple of 100 Quid Extra Tunnel charge that is not reasonably foreseeable and would not be recoverable in my opinion.
To be honest, if you paid £160 to join the AA and they either recovered you all resolved the issue, I think that’s an excellent deal and it would be cheaper than actually ringing a garage up to come out and do the job.
What the garage dealer said about everybody should have to be in the AA in any event is a complete and utter load of rubbish.
I would suggest that you write to the garage inappropriate terms and tell them that unless they agree to pay these costs you incurred in which you would not have incurred had they repaired the vehicle properly, you will take them to the Small Claims Court and that they have up to (say) 17 August 2018 to say whether they will after which you will issue Small Claims Court proceedings without further notice.
You can do it quickly and easily here
Can I clarify anything else for you?
I am happy to answer any specific points arising from this.
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