Well been to the garage. Saw the owner, who I haven't seen for years. He has turned into a grumpy old s****. He said: "Could be anything." I said, well that's why I brought the car along so you can check and diagnose the problem. Then he faffed around on the PC and said the oil hadn't changed for 18 months. I then asked him if he feels that would have a influence.
He waltz off out to the car and started it up and immediately said "engine wear", but stated that an oil change could solve the issue. I pointed out, as a carer, couldn't afford to pay for something if it didn't cure the problem. After more verbal flatulence by him I just said, "well, just do it..."
They gave it oil and petrol flush, changed a light bulb (didn't check the engine management light, as requested), new filter and fresh oil. The total bill came to £134.00. Has it stopped the problem? Nope.
Phoned them back to say it hadn't cured the knocking, and asked what would the next step be? They said it could be as little as £150.00 or, worst case scenario, £700.00.
Certainly wasn't happy with the customer service. I've been taking my cars there for the best part of 15 years, but they seem to have you by the short and curlies.