XType 2009 - Engine start up

[Jack Russell]

Just had a new alternator fitted, but each time I ow start the engine it fires up first time, but not on all cylinders until some 20 seconds have elapsed

Mechanic says nothing to do with his work

 

[Haiden]

I have the same issue on start up but does not last quite as long. But once running there no issues. I have had multiple diagnostics done but know one can find the issue. That's why I have turned to this site. I've spent thousands on the car, and I just want to get this issue fixed. Haiden