The gauges (rev counter, temp, fuel and speedo) intermittently stop working, and all fall back to zero, then start working again!, this can happen 4 times in a mile or not at all for several hundred miles. The car still drives fine and no warning lamps come on. Everything else i.e. dashboard lights, MFA still work fine even when the gauges are not. Anyone got any suggestions?

Mk1 Octavia Estate, 1.9 TDi, AGR engine

More than likely an issue with a dryjoint for the voltage regulator(s) on the dash PCB. Have a search on here, it is a well covered issue.