Ok I have two problems, both related to starting... Its my 1983 300sd

Issue one
This problem started before it got cold out, It used to take me 4 or 5 turns of the key to get the starter to spin. All lights would come on, and the interior light would dim down slightly, but no spin. Eventually i started taking 15-20 turns to start so i parked it because I didnt have time to work on it. Well its back on the road, taking 4-5 key turns. Suggestions on what this could be? I was thinking bad ground, bad starter solinoid, or bad starter. Since it does spin pretty fast once you get it to turn over I am doubting its the starter.


Issue two
Once I do get the car to turn over, the first start of the day in my mind is really bad. Over the summer my car would start fairly well with no glow, just an extra revolution or two. Now I wait for the glowplug light to go out, then wait 5-10 more sec and attempt to start. It will fire and die unless I rev it up slightly, and I have to keep it reved for 10-15sec or it dies after I let off. It then will die if I throw it right and gear and try to go immediately, so I let it idle for a few minutes. It does this the worst when its in the low 30's. The Glowplugs when tested from the relay ports all tested fine. And the interior lights dim down when I glow. What else should I be looking for?

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