Massive miss fire and loss of power??

I was driving back from Bristol Volksfest (sorry didn't know there was a OC Stand or I would have put my mk1 there!) I was almost home when there was a couple of big miss fires and a loss of power?

I only live just over a hour from the site so can't be from driving it to long on the day? I pulled in and it quickly sorted it self out but I'm kind of at a loss as to what it could be?? I've had a look under the bonnet and nothing seems out of place so it's confusing the hell out of me, unless the fuel pump is on its way out?

Cheers

Kieron

What car you got?
Year, engine size, fuel injection, carb?

Check fuel filler neck for rusty holes, dirty fuel tank, blocked fuel lines, old dissy, rotor arm, HT leads, spark plugs, etc….
Gives us a little more info on what you have done etc and we maybe able to answer or slim down what to look for or do.

Does the Car spin all the gears when you run the starter?  EX: Crank to Intermediate shaft to Cam?

I had the "Dad my car had a fit there was a ruff running bang and now it won't start.

The Timing Belt Broke.

Sorry that would be helpful!

It's a 2ltr 8v, p&p head with high lift cam from tsr. Still using the Kjet system. Then engine was rebuilt 2 years ago using all new parts.

Check that your fuel lines are blocked.  Classic Mk1 issue is that fuel tank ends up with bits of rust and dirt floating in it, usually from a rusty filler neck.

I recently changed mine and it now behaves as you describe.  Removing the filler cap, splitting the fuel line and sending some air down there clears it temporarily (may not on an injected model) but my fuel filter visually fills up with crud quickly.

Fix is fairly easy, there is an inspection hatch for the fuel tank under the rear seat.  Pull this then remove the bayonet fit plastic fuel sender cap underneath and take a look.  Remember: no spakrs, no naked flames.  Be careful not to damage the fuel level sensor when you extract it.

What year is the car and is it a cabriolet or tintop?
If tank and filler are hole/rust free is it the original  or replacement fuel tank and how much petrol was showing on the gauge, did it misfire when cornering or just after?
 

It's a 1982 tin top. It had a new tank 4 years ago so shouldn't be that bad? As for when it happened I was on a straight