I have a A140 (1999) which I had to change the battery in due to going to the car each time after not using it for a couple of days and finding it dead. When I had changed I went out for a short run and it was fine, now when I drive it it judders and looses power, 20 mph max. The battery has been tested and the sparks and coil changed. The dignostic computer has bought up lamba sensor but from reading postings it does not seem the same symptoms. Can anybody help?