Car wont start first time in cold weather - what needs fixing?

How they fit is pretty irrelevent to whether they're any good or not because its the quality of the insulation thats the issue.

If the car hasn't been serviced for a time then it could be ready for the plugs changing. This should be done every 10 000 miles or once a year. The carbon cores inside the plug leads also break down over time and build up too much resistance. These need changing every 10 000 miles along with the plugs - also the air filter. I changed these 3 items on my wife's Micra at the weekend and it's like a different car.

If your battery is getting on a bit it might not be able to supply sufficient power on very cold mornings. As you don't give any details about your car (age, service record) it's very much guesswork.

Hope this helps

Also sprach "Raymond Berry" :-

Far more likely is that the insulation breaks down and the spark "leaks out". In bad cases if you wait till dark you can see the leads glowing!

As a short term fix, removing the leads and wiping 'em over with a WD40ish cloth and cleaning the plugs, dist cap and lead ends with the same can keep you going for another six months. Or six days, depending on luck.

OT but where did you get the plug spanner for a micra? It must be about a foot long!

Snipped

I use a socket type plug spanner on a long extension for my Primera but due to the rubber insert it kept hanging on to the plug and pulling the socket of the extension so I had to put a weld on it to keep it together so dont use your only extension.

Trevor Smith

You're right! Not sure what the proper name is for the tool, but it's a long, single tube with a built-in tommy bar at one end and the other end is socket-shaped . It's a proper plug spanner as it's got the rubber insert to grip the plug. I got it from Halfords a few years ago.