Astra Flickering Lights - Mobile Office

Have a 2000 1.7DTi Astra (isuzu lump). Lovely car but has a more often than not a flickering light problem. It affects all lights from headlights to interior light and dash lights and gets worse with load. Garage says alternator is within spec, but surely its not right. With a meter across the battery, with no load its charging at nearly 14.5v with a full load its about 12.2v. Whilst lights are flickering voltage oscillates about 0.6-0.8v. I suspect voltage regulator but any ideas? Or is the garage fobbing me off as its under warranty.
Astra Flickering Lights - Aprilia
Certainly sounds like a voltage reg. problem.
Astra Flickering Lights - Peter D
Check any earth straps for continuity and corrosion at the bolts. IF the car has done 60k then it could be the regulator brushes are away. Yoo mention 12.2 on full load but I assume this is at tick over as it should not drop below 12.6 and ideally 13.2 at 2 rpm. Regards Peter
Astra Flickering Lights - EnormousDerek
Yes mate, sounds like your voltage reg. could be a bit flakey. Either that or a diode going. Maybe a dry joint somewhere in the alternator.

The alternator on my Cav 1.7TD (Isuzu engine) has packed in twice; first the bearings went at about 150k miles, then the voltage regulator a couple of weeks later. A geezer in a little workshop in my local town put a new one in for £28. It was another £28 for the bearings. A bargain, since a new alternator was to be £179 exchange from the Vauxhall dealer. The only problem is getting the thing off the car (2 drive belts and 2 oil pipes to disconnect), but it's pretty easy once you've done it a couple of times. Watch out for the vacuum pump; it's full of oil when you take it off!