I'm sure your mechanic has likely checked this, but are the spark plugs connected to the right plugs and the corresponding points on the dizzy cap? Other thing, if you've recently done a timing belt, is maybe check that the timing marks are lined up correctly, as they can normally run okay when they're one or two teeth out. More than that and it'll either run like a pig or not at all.

Also, try a diagnostics test. Only tool you'll need is a paperclip or a short length of wire and this guide: https://www.corsa-b.uk/forum/viewtopic.php?t=11231

Personally, I'd be binning the C14NZ in favour of a 1.8L Z18XE from an Astra, it's an easy swap, but some of the parts required aren't easy to find these days.
Click here to enlarge Warning: This is an Old Thread
This discussion is older than 120 days. information contained in it may no longer be current . Please think of the children before resurrecting this ancient thread!