On my 85 617 there are 2 temp sensors on the left side of the engine between the # 1 & #2 glow plug and one between #2 & #3 plug. one is the temp sender & the other is for the temp sender for the glow plugs.
switch the wires, both senders wouldn`t be bad.

Don`t know about the 91 350, so just a guess.

Charlie ☺

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works