V8 only firing on 4 cylinders, r129 129.066

[isobars]

Hi All,

I'm unable to find any info on this. The coil and leads have been changed and checked on the other side, so is it the brain-box?
Thanks very much in advance for any help.
Cheers,
Paul

 

[ivan1983]

Might be worth clarifying the engine type I'm guessing it's a M119 with distributors rather than coil over spark plugs?
Do you know what cylinders are not firing and how have you determined this?

 

[slsteve]

If it is a M119 engine? Remove the distributer caps, check for wear and clean them. Smear some silicone grease around the mating surfaces before you replace the caps.
A known issue with this engine is condensation in the distributer caps, I had the same issue with my SL500.
Hope this is all it is and this works.

 

[BlackC55]

Do some basic checks first. Check for a spark and go from there.

 

[alabbasi]

Assuming that it's an earlier M119 motor which have two distributors driving 4 cylinders each. I would check cap and rotor and the insulator. It's unlikely that it's the wires or plugs themselves if all 4 are gone.