'03 156 JTS engine issues
I've got an '03 156 JTS with 90,000 miles and was dealer serviced until 60,000 miles. The previous owner did the timing belt around 15,000 miles ago but I think he got it done at a friends garage or somewhere dubious, no receipts, etc.
The problems are firstly it's hard to start and it takes a good 6-7 seconds of cranking and then it splutters and slowly gets up to idle speed. Secondly, the engine pings quite a lot under even mild acceleration, despite using high grade unleaded fuel.
The question is, could these problems be caused by an incorrectly fitted timing belt that was installed a tooth or two out?
Could they also be caused by the cam-lobe wearing problem in these engines, which I believe affects cylinder No. 1 ??
If not, what are the other potential causes?