My original OD solenoid (BJ8 phase 1) has been acting wankie recently. It works fine 95% of the time then won kick in. I found that if I remove the rubber boot and give it a tap with a wood dowel it is fine for days. It may just be hanging up on dirt or something. I purchased a replacement from some third world country but haven't installed it yet. I'm thinking the original may just need the "piston" lubricated with some white grease. I am running mostly original and would like to keep it that way. Has anyone experienced a problem like this and solved it with just servicing it?