All of the pins are the same on these. You might have a problem. Look in the connector to determine if some of the female ends are missing.
I would use the black vacuum hose found in an automotive parts depot. The tighter they fit, the better. Also, I have been known to use a little drip of Super Glue to adhere the connection.
1992 500E (very soon I hope
1981 280GE SWB
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