The old elec PAS on Vauxhalls do suffer pretty badly from overheating. Especially badly at full lock. Every one I've driven for a reasonable period (the missus had 2 and my sister had 1) has failed until it cooled due to overheating. The early vauxhall ones are very temperamental, and pull to the side/much easier to steer to one side as well. Even when someone went into the front wing of my missus's car, the garage advised its not worth looking at when we told them that the steering was heavy on that side (even though we knew before it had happened) as its a very common problem. Vauxhall never really dealt with the issue at the time so no real fix tbh. Have a search for those specific things as I did when first driving one. Threw up tons of examples....