Missfire perhaps.

[Ade]

Hi all,
I thought I had fixed this problem. After starting the car and in the first few hundred yards there is what I can only discribe as a sudden missfire, just the one but more like a loss of power for just a fraction of a second, and usually on a gear change. It happens just the once then it runs fine.
I have changed the plugs to no effect. I changed the CAS and the CTS and it seemed to have fixed the problem. It as run really well for over a week now but tonight after filling up with fuel it did it again, just the once. Could it be bad fuel or as anyone else experienced this fault.

Thanks in anticipation.
Ade.