If your car is pre 89 you have a "hall" sensor inside the distributor which often fails at higher mileage. When turning engine on starter, look at rev counter. If it flickers chances are the sensor is OK. If it's dead suspect sensor. I assume you've checked leads and connections first and maybe connected a plug direct to coil HT to eliminate dist. cap. The sensor can be checked electrically if you remove the dist. FAQ's have good section on this. Good luck.