I pulled out my RPR parts catalog.
Eric prob remembers RPR and Rusty's comprehensive parts catalog.

anyway
p68 in the ignition parts section.

240 83-84, B23F w/Bosch distrib

Impulse Coil or Reluctor(sender): Volvo pn 1336462

I haven't a clue but RPR sold Volvo parts...genuine BlueBox Volvo parts.

This part was only used in those 2 years on the B23F ignition system.

ps: the number for Chrysler distrib is 1332207 --- in case you run across that number in your search

I still think it will turn out NOT to be a faulty Hall Sensor...but then that's only from my single experience. FWIW the Hall Sensor for my 87 245 B230F cost me $89.99 from RPR - in late 1990's Dollars.
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RPR Volvo parts follow up April 2011

I went to RPR Volvo Discount parts in Albany, Ca. yesterday-bought a new "made in Germany" water pump almost 1/2 price just to stock up since RPR is closing down in about 6 weeks permanently-I previously went in and bought about $200 worth of parts-like filters, belts, hoses, dist caps, rotors etc-and saved a bundle of $$$. He is even selling his desk manuals, and, I even got a "Volvo" necktie for $5.

Question is-where do I shop for parts locally after he is gone?? and I dont mean the internet-the 'net is fine but when I need a part now-I need it "now".

https://www.brickboard.com/RWD/volvo/1480402/rpr_volvo_parts_follow.html