Rover 200 & 400 Owners Club

Hello mates!
I feel something wrong in this video:
https://e.pcloud.link/publink/show?code ... LA4RjUKB9k
It looks a cylinder isn't working well. I'm guessing it might be a defective spark plug.
The last time I swapped them was in Feb 2020, i.e. 6 years and a half.
But the car has done only 31,000 km / 20,000 mls.
They are good ones: Bosch double platinum ref. 0242236544 fully compatible with Rover Fr7Kpp33U+.
In what direction should I go?
Thanks a lot.
Arnaud from France

I've had spark plugs fail, even relatively new ones, they discharge internally rather than at the spark gap. Had a problem with a Bosch sparking plug on my 214 like this, it was however made in Russia ... I've also had a similar problem due to faulty ignition leads, they can go high resistance so that less or no HT gets through. They will normally by 3k to 10k ohm measured with a multimeter. If it's a lot higher than that, the lead is faulty. Also is it possible one of the injectors is misbehaving. I'm assuming the rest of the engine is healthy, no signs of HGF or low compression on one of the cylinders.

Thank you mate.
Since a few days the engine was misbehaving like that but until that all was fine and the car is duly well serviced and controlled.
It's the missus' car since 2015.
No HGF at all (all gaskets and the likes renewed in 2020), levels are fine, no leaks and the car doesn't miss a beat.
It's just worrying but mainly when starting off and firing hardly at once, but on the third attempt now mainly.