metro wont start backfire through throttle body

hello:
i have a 93 metro, 1.0 liter fuel injected, that wont start. i drove it to
work and it ran fine. when i came out to go home it wouldnt start. it
did not appear to fire at all, but when i checked the spark at plugs i
had good spark. i changed spark plugs anyway and it began to backfire
through the throttle body.
i have checked the distributor and timing belt settings and they look
good.
i have one book that says there is a crankshaft position sensor in the
distributor, this controls the ejector and ignition timing via the computer?
it says that if this is bad the car wont start!
however, none of the books i have tell how to fix or test this.

also, if anyone has any other ideas of what might be wrong i would
appreciate the help.

thanks

I have never found a reliable way to test a hall sensor. But at the same time, i've never seen one go bad. You may have skipped a tooth on the timing belt. But first, buy a new sensor and toss it in. If it still doesn't work, clean it up and take it back ;). Are you sure it's getting fuel?

if your getting spark the sensor in the distributor is fine. take a real good look at the cap and rotor and make sure you don't have moisture inside the cap or arc tracks. also seen a few rotors that the center gets eaten away in the middle. if they look good and it still won't start i would suspect the belt has jumped a few teeth or something is wrong with the computer

try unplugging the map sensor. It is located on the firewall of the vehicle.
My car did that and it was the map sensor. The car will not start if the sensor is bad. if the car starts and runs with sensor unplugged, that is your problem.