Not really, as the ISCV is just one part of it, the enrichment side sounds like it's working fine.

Tbh it may be worth asking a specialist, as you can carry on throwing money at things that arn't broken. It may even be a faulty PCM.

It's kind of hard to know the voltage is ok as it's controlled by PWM, it's impossible to judge accuratly with just a multi meter, an ocilliscope or NOID light is a better bet.

It's worth removing the valve and blanking the hole with another (If you still have one) or something else, just so long as it's substantial so it dosen't get sucked in, and visually examine the valve operation.

Martin