Hey all,
I've got a 1984 240 Volvo. Recently, I went over a speed bump and my car stopped working. (the car did not bottom out, just the action of my front wheels going over the speed bump). All the lights on the dash came on, and my car will no longer turn over. Upon inspecting, I found that I'm getting power all the way to the distributor, but no power to my spark plugs. The spark plugs are very new as well as my battery. Does anyone have any ideas of what could be wrong or have experienced something like this? Thanks!

 

Did you check for spark while it was cranking or just with the engine off? Is there no power to any of the spark plugs or just 1? Cap and rotors aren't too bad of a price if they do need replacement.

As you probably know, you would need the engine to be cranking to check for power to the plugs as no power will be sent without it moving.

 

If you are getting a spark out of the coil and have it at the distributor, but don't have a spark at the spark plugs - your rotor button could be bad. The built in resistor can fail and not transfer the spark from the center of the rotor button to the tip where it is sent to the poles inside the cap. Or the cap itself could have tracking inside where the spark is being sent to ground instead of going to through the wires to the plugs.

Of course a rotor button is generally not going to fail by going over a speed bump, so maybe we should look elsewhere. If a older 240 dies (engine stalls but starter will still spin engine over) after going over a speed bump I would look for problems with the wiring - after I checked the fuel pump, by listening for it to come on, check for spark with a test light - should be a flash on one side of the coil as the engine is spinning over, and checking for injector pulse with a noid light. Visually, the engine harness traditionally loses/shreds insulation near the multi-connector plug at the back of the valve cover and shorts several wires together, and for the distributor the plastic connector on the side of the distributor breaks and can ground out those small wires preventing the ignition system from firing.