Thank you for all your responses, the car was registered March 1994, I'm getting it back tomorrow so I should get the readings then. I was talking to a friend today who has a mechanic friend who had a 300 for a few years until recently so I'm going to talk to him. All your comments help and hopefully he can too. The car is really sound and I've had some very reliable motoring with it so I hope I can get it fixed !
I've had a Sylvia, 200SX and the 300 and now I've got a 350Z so I really love Nissans !