misfiring when cold/"pinking"

[rwaw]

Hi all,

My 69 280SL starts all the time/everytime but when cold coughs/splutters/hesitates for about 10min. After that all's well.
Secondly depressing the throttle for anything more than about 1/3 lead to loud "pinking".
Local MB dealer says can't eleminate pinking altogether because performance would suffer too much.
How does this sound to you experts ?
Any suggestions re the misfiring when cold ?
Anybody know any good specialists in North East England ? (local MB dealer tries to be helpful but I'm not sure how much knowledge they have in house)
Thanks.

[Naj ✝︎]

rwaw,
Could be a combination of problems.
What's the Bosch part number on the distributor body?
Also the cold start circuit may not be working. Would have to check thermostat on the injection pump and cold start valve operation.
These items have been discussed here before but its a start.
Hope it helps
naj

naj
'Kloines Scheisserle'
65 230SL
68 280SL

[Cees Klumper]

I used to experience stumble/hesitation/rough running when the engine was cold (only the first 30 or so seconds though, and the cold start systems checked out ok then), and at high RPM (>4500) when the engine was at operating temp - it was finally eliminated when the engine head was reconditioned. This was necessitated when the head gasket developed a leak.
My car never 'pinks' and, despite the engine having rather poor compression, still pulls pretty strong.