After reading about your symptoms, I'd say their is a possibility it could be either a bad computer (ECU) or a bad 25 amp fuel injection fuse. Been there with the bad fuse.

I agree with Yama, if you haven't already checked the computer (ECU) to see if it is a bogus definitely do that. Bear in mind that the 1989's and some 1990's have the bad computer as Yama mentioned. White label is good. Think the good part# is 900 something.

Any competent mechanic should be able to find a bad computer. If you find a reasonably priced white label computer on your own, it is a snap to switch them yourself. No need for a mechanic.

In a related earlier post -
Pageda mentioned the fuse located behind the battery in his post. Check this fuse first before spending any money on a computer. It is NOT a battery fuse. It is a 25 amp blade style fuse that protects the computer on 1990 and older 240's with the LH 2.4 fuel injection system. Sometimes called the fuel injection fuse. With its exposure to the weather, this fuse and its plastic fuseholder will eventually deteriorate. A bad fuse/fuseholder can cause the running problems you have described since the signal to the computer will be intermittent if the fuse or fuseholder are bad.

While there, also check the conditions of the wires that run from the fuseholder to the battery. On my car these wires are red in color. Clean and reattach securely or replace if needed.

As mentioned I had a similar problem with the fuse/fuseholder on my 1990. Running problems. Replaced both. No issues since. 1990 is a good year. I have 300K on mine and it still runs well. Needs some other work but the engine runs great....:)

Please find a 240 specialist.

Good Luck!

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95 855 GLT Sportwagon, 93 854 GLT (for sale), 90 244 DL 300k :)