my car will run fine until its driven for about 30 minutes then it will miss very bad, it seems its getting too much fuel, because it will start to smoke black smoke, could this be the switch over valve, vacume advance or what. I welcome any suggestions.
1973 mercedes 450sl
Aug 09, 2006
3 Replies
Black smoke from a gas engine is over fueling - for sure. The motor's cold start fuel enrichment is stuck ON - starts fine when cold but chokes when hot.
Try disconnecting the connector going to the cold start injector (next to the idle adjustment), and see if that stops the smoking.
does it matter that my 450 is electronic fuel injected instead of manual? Does the start valve also have a vacume diaphram in it? How hard is it to find and change? Thanks for your input.
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