Intermittent ABS warning light
 

The ABS side of things on my W-reg UK Impreza Turbo was absolutely fine until I replaced the knackered front calipers, discs, pads, shoes and replaced the brake fluid.

After the above work, sometimes I had the ABS light come on during long A-road dual carriageway drives, normally after about 20 to 30-odd miles driving at a constant 80mph or so.

I pulled the rear discs off again as there was a lot of rust and crud in the originals, so thought that I might have some dirty sensors, which I cleaned up and thought I'd gotten rid of the problem. A couple of 50-mile back road drives at varying speeds later and no ABS light, so I was pleased.

But a couple of 50-mile boring dual carriageway drives at higher speeds saw the light coming back on after the normal 20 to 30-odd miles. The odd thing is that after stopping the engine for a bit and then starting back up, the ABS light remains on but extinguishes a few seconds after getting on the move again.

I've not tested for any codes yet, but can anyone give me some pointers on why I've got this odd ABS problem? Maybe I should give the front ABS sensors a bit of a clean from rust and crud as well? I've also not tested whether the wheels will lock up with the ABS light on either.

Thanks in advance for any help.