Truns over but want crank
An engine spinning just means your battery is good and starter works. You'll need to find out if you're getting the other things you need. Those being air, fuel, and spark.
For air, take the air filter out of the picture by removing the air flow going to the carb. Try to start the car.
if it doesn't start, for Fuel, try spraying into the carb some starting fluid then try starting the car. Does it run for a little bit with the starting fluid you just sprayed in there? If so, you've probably got a fuel problem.
If the engine still won't start, take one spark plug out and keep the spark plug wire attached to it. Make sure the spark plug is touching metal so it's grouned electrically, like laying against the engine block. Don't hold the spark plug because you can get a good shock if you hold it wrong. Just lay it on the engine block. Ttry starting the engine and watch for spark at the end of the spark plug. Sometimes the spark is hard to see so doing this at night or in a garage will make it easier to see the spark which leads me to another point. Sometimes your sparkplug wires get so old they electrically aren't any good anymore. You'll be able to know that if you start your car at night and you look under the hood and see little sparks jumping from your spark plug wires to ground. This means your spark plug wires need replacing and that could be your problem. Usually the engine will run when this happens but it won't run very good as most of the spark is being shorted out.
So try to isolate where the problem is...Air, Fuel, or Spark and go from there.
GMC Yukon Denali...
on Jun 29, 2014