Is there a trick to removing the 4 pin connector plug on the shut off valve?
It will not just pull off. There is a thin metal band around the end, does that need to be pried off first? 1999 E300.

If it's like gasser injectors, removing or at least partially removing the metal band will allow you to pull off the connector.

Sixto
98 E320s sedan and wagon

Feel around the perimeter of the connector for a tab. Try carefully rotating that tab counterclockwise. I believe this is a bayonet lock connector, the collar rotates a quarter turn, which unlocks the connector to allow it to be unplugged. Similar style connector to what is used at the transmission.

When you go to plug it back in you'll need to line up the pins as well as the slot on the collar, carefully push in while rotating the collar back to the locked position.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

IIRC that ring acts as a "spring". Pretty sure it just pulls straight off to remove.

__________________
Jim

As above , always just pulled it off

It's just snapped on, no tricks. I usually just pull and wiggle the connector back and forth until it comes off.

Take care when you're pulling that: 1. You're not pulling so hard that your hand smashes into something sharp when it lets go and 2. When it lets go, you don't rip the connector off the wire.

This is just a complicated way of saying to have control of your hand when pulling.

__________________
-Evan


Benz Fleet:
1968 UNIMOG 404.114
1998 E300
2008 E63


Non-Benz Fleet:
1992 Aerostar
1993 MR2
2000 F250

As above, the ring sits over a small plastic lip, can be tricky to remove though - try using a large rag to grasp it, if that fails very gentle tap with socket extension or similar just to free it up a little.

__________________
David


1996 Mercedes S124 E300TD - 129k - rolling restoration project -

1998 Mercedes W210 300TD - 118k (assimilated into above vehicle)