How accurate are C5 tire pressure sensors?

[Monk]

I'm sure this has been asked before, but I can't seem to find it in the archives. How accurate are first and second generation C5 tire pressure sensors? Does the accuracy tend to fade (i.e., readings drift) over time? Do C5 owners tend to rely on their internal tire pressure sensors when setting air pressure... or precision hand-held gages? I am finding some small disagreement between my sensors and my hand held gage. Of course, the fact that I only paid 99 cents for my tire pressure gage may be part of the problem! :yesnod: :yesnod: :yesnod:

[Gearhead Jim]

The sensors on my car initially agreed perfectly with my 3 different Radio Shack digital gauges. After almost 2 years and 30,000 miles, the rear sensors are now sometimes + or - a couple of pounds, depending on which wheel is involved. Fronts still seem perfect. And no, I don't do a lot of burnouts.....