So I was running my campaigns without "conversion tracking" in adwords enabled, my Quality Score was perfect 10/10 for about 5 months. I thought of experimenting and enabled tracking from inside adwords and bam just after 2 weeks QS was down to 7/10 ... I have disabled it again now and hoping goes back to 10. just a heads up ... Let me know if someone else has faced something similar.
yeah, it's something else, not tracking that's done this - most likely it's a dip in CTR compared to your competitors (maybe competitors testing new ads with better offers, free delivery etc etc)
QS has nothing to do with the conversion tracking code. You need to analyse more and see what has gone wrong. If you haven't made any changes to your landing page or ad copy, then definitely its the competitors who are winning.
Somehow GA was not able to track the conversions on my site properly, for every 10 conversions it was just tracking 1, so Cost/Conversion went way high and may be that triggered GA to conclude that mine was not a "Quality" site. Having said that, I agree GA has made quite clear in some of the references that conversion tracking won't effect the QS. But given all factors the same, I have to arrive at this conclusion. I am waiting for a week or so to see if I get my QS back. I "ll try to keep you guys updated.