1.2 HTP Tensioner upgrade date

Hi all,

Apologies if this has been asked before, or if I've asked in the wrong place, I'm new here!

I've been keenly scouring the used car ads for a fabia mk1 for my partner to learn to drive in. The low insurance group of the 1.2 HTP has great appeal, but in the price range we're looking at we end up straddling the 2003/04 line. I'm aware that around this time there was an upgrade to the timing chain tensioner to solve some nasty issues with jumping chains! Obviously I'd like to avoid buying one of the pre-update cars, but I've yet to find a precise way to find out whether the engine has the fix or not.

Is there a way to tell? Engine serial numbers, a month of manufacture from when it was introduced? 

Cheers for reading,

A prospective skoda owner