Puggsley

I had the clutch replaced on my RX8 (04 Model) on Friday and since then have had several issues which hopefully someone with better knowledge of the car will be able to help with

The clutch was replaced by a well known car garage with a decent reputation but they are still unable to correct the issues.

After getting the clutch replaced I went away for the weekend so drove approx 100 miles, mostly motorway. The car seemed quite unresponsive when accelerating and produced a loud banging noise when applying anything more than a light touch to the accelerator when in 4th or 5th gear. At this point I was thinking I'll just take the car back monday morning and get it checked again, but when I went to come home with the car on Sunday the car would turn over but not start. Assuming the engine had flooded I went through the procedure for clearing it but had no success, and called the AA to look at the issue. After nearly an hour of trying to start the he eventually tried to start the car while towing, which it did eventually.

After this I drove the car back home without any further issues. The banging had gone but acceleration was still really bad

I took it back to the garage and after a couple of hours they called to say they had knocked a "plug wire" (The What?) which was causing all the problems. I didnt believe them so took it far a drive to test acceleration properly

As the issue is worst in higher gears I tested accelerating from 60mph to 70mpg.

In 4th gear this seems OK but results in a coolant level warning, which I have checked and is OK.

In 5th gear it takes almost 30 seconds to get from 60mph to 70mph with my foot flat on the floor.

Has anyone got any ideas before I take the car back to the garage in the morning?