Not sure if its the same issue or not but Mel had some probs with her 7, this is from facebook by one of her friends and has seemed to fix the problem... Hope This Helps??? And sorry for the copy from your wall Mel but it may or may not be helpful
"Just read u had a hard time with the 7 and a doddgy start solenoid on the weekend, sorry to hear that.
Dont know if ive told you before but i am an auto electrician by trade.
Ive had alot of experience with this kind of problem with kwakas.... The solenoid is also an ignition relay and is a very crappy design and made cheaply. They use the same type on 6's , 7's and 9's of that period so ive seen alot of them fail.
However the solenoid its self is not always the cause of the problem, the main problem is usually the wiring plug ( red plug ) that is connected to the solenoid.
Did the solenoid melt/burn where the red plug is connected to it ?
The wiring terminals that are inside that red plug are shit house ! they corrode very badly and get loose which means they dont connect to the pins on the solenoid properly ..
This bad connection gets very hot and normally melts the solenoid and the red plug.
If it did melt at the red plug then i cant stress how important it is that you not only fit a new solenoid but you also change the crimp terminals inside the red plug , Its a very quick and easy job.
I have lost count of the number of times i have seen people simply change the solenoid and then it melts again because they didnt fix the plug connections."