From the description of the balancer coming loose I suspect the crank sensor rotor on the timing belt pulley moved enough it damaged the crank sensor. The sensor sets over the rotor and it passes through a gap in the sensor, if the balancer came off the belt pulley could shift enough that the sensor was damaged by the rotor. There is also a locator pin that holds the rotor to the timing belt pulley, if the rotor was bound enough it may have sheared. A quick test to see if it's working at all is to look at the tach while cranking the engine, does it move as the engine turns? No or bouncy = sensor damaged. If the pin is sheared the tach may still move but the spark will be out of time. Without the signal the engine will not start, if it failed while the engine was running it will keep running, but then will not start after being shut off.
To get to it to see if that is the problem you need to remove the lower timing belt cover and get to the sensor, it can be replaced by removing the connector and the screws. I would also check the timing belt alignment and probably remove the timing belt just to check the rotor pin, and the keys that hold everything in place. With the bolt loose the keys may have started to shear which can throw the cam timing off. Once you repair that be sure to install a new damper bolt as they are a single use fastener and get torqued to 130 ft lb. If the timing belt hasn't been changed this would be a good time to do all of it, including changing out the water pump.
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Sep 3, 2021 at 2:44 AM
