Rain causing weak spark/not starting?

[Gavin583]

Had to leave the car sitting outside past week and was driving it everyday, went out on Sunday morning and car wouldn't start. Was cranking fine but no sound of it starting.

I was out in the car Saturday night and has been running great since getting it back on the road a few weeks ago.

Took the leads off and put a screwdriver up the lead and was weak spark to the block.

With the heavy rain and bank holiday cleared out the garage and left it inside for a few nights to dry out before buying parts.

Car started fine tonight and spark from the leads is strong again so guessing rain or damp got in with the storm we've been having.

Having a look around the coil and distributor cap don't have shrouds over them so thinking water got in from the passenger side engine lit vent and got in some how or something else got damp causing weak spark.

I didn't pull the cap off on Sunday when I put it in the garage but pulled it off this evening to have a look and it was dry which makes senee since it started after.

Anyone have any similar issues?
If any sort of shroids are available? I'm assuming it was the coil or distributor cap.

I know the proper answer is keep it garaged but was grand past 2 weeks and In this climate you can never trust the weather, really wouldn't want it happening away from home lol

[MGBENG]

Hi Gavin, I had similar symptoms to you. I changed the coil and that solved the problem.

[_Al_]

ECU capacitor aging may exacerbate the failure, but I’m voting coil as well. They can crack with age and let moisture in.

[Gavin583]

Sorry forgot to get back.

Yeah seems it was the coil. Put a plastic bag over the coil pack under the fuse box and haven't had any issues.

Bit hooky but works as a proof of concept I'll put a new one in at some stage aha

[jimi]

Good enough to diagnose the problem, lets you use the car and gives you time to find and fit a replacement. Nothing wrong with that