Thanks folks, I'll try the injector flush.
with regard to it missing - I have replaced all of the electrical side, it's sparking on all 6.
It's only slightly lumpy at idle - perfect otherwise.

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Mercedes Benz 300sel. 309,000 miles (What that is in km I don't know) - My workhorse, faultless mile eater that refuses to die.

TVR Chimaera...4.0V8 A whole bundle of tailsliding fun.

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