Recently car has developed jerking jumping whilst driving. Starts in lower gears mainly and has a reduced power for acceleration. Took it to my usual garage who changed a coil and tested the others and they thought that had resolved it but when I drove home same happened. The garage ran diagnostic but no error codes were showing, have advised they cannot find any fault and to either drive until error codes come up or take to Tenault for full diagnostic testing. Any suggestions? No fancy jargon or abbreviations I am a novice so don’t understand it all! Thanks in advance. By the way, not sure if it’s related but the exhaust fumes don’t smelll as petrolly as they usually do!?