Had car about two years. Would start fine in first year but from last winter with all that rain, it just wont start if there is any hint of dampness in the air. Let the sun shine on it for couple hours and it starts fine. If its rainy forget it. If driving to Sainsburys, couple miles, and it starts raining car will restart, but is that because engine is still warm and therefore dry?
I am hoping this is something really simple. l checked the lpugs and they look fine. Thats about all l know how to do on this car. Dont know the correct plug gap though. Appreciate any replys. Ta muchly.

spray distributor cap and leads with damp start

Not familiar with that model but a J reg may well have a distributor. If it does change the cap, sounds as though there is dampness inside it and/or it is tracking.
Get a sealant spray and spray all your ignition and distributor leads as well

l agree with poster one. Spray all the leads with a spray to stop damp getting in there. Sometimes if you look under the bonnet at night while someone starts the engine you can even see sparks arcing across the leads.
The leads may need replacing. Any decent garage will, measure the resistance for you.

Could help;

http://htdig.honestjohn.co.uk/forum/post/index.htm?t=61766

The plug leads (''HT leads'') deteriorate over time, they're sort of rubber so perish & crack, then the damp gets into the cracks & allows the spark to escape rather than go to the spark plug.

If spraying with WD40 or other similar water repellent spray helps, then replace the leads to avoid having to respray every few days or weeks.

The distributor cap (if it is the sort with a distributor) can also be a problem, so maybe replace that as well.

When replacing the leads, do one at a time, so u do not mix up which goes where.

It is only a 5 minutes job, maybe £10 for the leads, & u will hardly get ur hands dirty. Money & time well spent.

give the leads and cap a good wipe Before spaying wd40 ,
good luck h