1991 was the third year of that bracket.

Read Onkel's response to someone that had the same problem, yet Onkel also indicates checking fuses.
https://www.brickboard.com/RWD/volvo/1600597/93_volvo_240_wagon_stalls_driving.html

Depending on where you reside, that bolt snapping may attributable to corrosion forging in the screw / bracket hole thread interface. Sorry that happened to you.

As for stalling, I'd rather you disconnect, apply some DeoxIT-D to one contact side or another, and reconnect the two. The ignition amplifier is merely that, a solid state signal amplifier like that in your car stereo.

As for your mystery stalling and no DTC (diagnostic trouble codes) in socket two (fuel control) and socket six (ignition control), your stalling experience is disconcerting!

I would consider causes that are outside the engine control logic, or may be part of engine control, like a connection, yet not monitored by engine control to spawn DTC fault codes and a check engine light.

Your stalling is intermittent, so electrics as something to inspect. If you reside in an rust belt region, grounds and connection are good to inspect, clean, and reconnect. Be gentle with 30-year old plastic. Closely inspect the fuse box and give them a spin. More than one person here has disconnected a battery, remove fuses, clean the clips, and put the fuses back in with a touch of grease at each end (or on the clip).

How many mile on your 1991 Volvo 240? Sedan or wagon? Automatic or manual gearbox transmission? How old are your motor mounts? Phil Machine Man asked whether you have EGR or not.

Does your 240 stall when you press the gas pedal or release it? What is your speed? It helps to know whether you reside in the Atlantic Northeast like many here or in the rust-less Dessert Southwest?

Questions?

Hope that helps. Please reply.

Thank you.

And välkommen to the brickboard!!!!



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