Well... Now my brakes are back to almost normal, I can return to this. I have booked an MOT for Thursday - to see if it'll pass emissions, but should it fail (it still has that odd misfire) I still have a few ideas, before I rebuild the motor.

It could be some of the following so I am looking for advice on how to test these in the best way possible ideally without £400 smoke machines or emissions testers.

Spark Plugs - I am going to take them out and get pictures of each one, one by one, to compare them and see if there is too much fuel / not enough / oil and or coolant etc

HT Leads - This I am not sure how to test without simply replacing them. - but may be worth cleaning the ground attached to the gearbox as that is connected through to the HT leads...?

Distributor cap - I am sure this won't be the issue - Because I replaced it about a year ago now, though I suppose I have been green-laning / off roading a few times since so it is possible dirt or debris got in there? I will go in and take a look.

Rotor arm - Again I think this is unlikely as like the previous one I replaced this about 12 months ago... But I am sure I will look into that when taking the dizzy cap off.

Distributor shaft play - Will check again.

Wiring & grounds - As mentioned I will probably remove the gearbox ground and some other grounds I can find to clean them and try again.

Vacuum lines - I will spray all the vacuum lines I can find with brake clean to see if I can find a leak (increase of revs).


If anyone has anything else I can check, please let me know before I spend ~£1500 on an motor rebuild as realistically I don't want to do that soon, eventually though :)
 
Well... Now my brakes are back to almost normal, I can return to this. I have booked an MOT for Thursday - to see if it'll pass emissions, but should it fail (it still has that odd misfire) I still have a few ideas, before I rebuild the motor.

It could be some of the following so I am looking for advice on how to test these in the best way possible ideally without £400 smoke machines or emissions testers.

Spark Plugs - I am going to take them out and get pictures of each one, one by one, to compare them and see if there is too much fuel / not enough / oil and or coolant etc

HT Leads - This I am not sure how to test without simply replacing them. - but may be worth cleaning the ground attached to the gearbox as that is connected through to the HT leads...?

Distributor cap - I am sure this won't be the issue - Because I replaced it about a year ago now, though I suppose I have been green-laning / off roading a few times since so it is possible dirt or debris got in there? I will go in and take a look.

Rotor arm - Again I think this is unlikely as like the previous one I replaced this about 12 months ago... But I am sure I will look into that when taking the dizzy cap off.

Distributor shaft play - Will check again.

Wiring & grounds - As mentioned I will probably remove the gearbox ground and some other grounds I can find to clean them and try again.

Vacuum lines - I will spray all the vacuum lines I can find with brake clean to see if I can find a leak (increase of revs).


If anyone has anything else I can check, please let me know before I spend ~£1500 on an motor rebuild as realistically I don't want to do that soon, eventually though :)

Just bring it along in a few weeks… 😉

Given that you’ve replaced the dizzy etc., and it’s a keeper, I think I’d put new HT leads on it anyway, if it were mine. Depending on the plug conditions, those also.

To check the main earth/s, I guess you could always use another cable for testing (a jump lead?) and see if it improves the situation.
 
Welp, guess I'm towing it down, it seems the misfire in the previous posts is causing the issue - I've attached a picture of the emissions test - checked all plugs and they not only look good but actually quite good no wetness or fouling, so really am lost and will let all all have a gander at it.
 

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