4 Things an Engine Needs in order to Run

4 Things an engine needs in order to runMy 2000 Saturn SL2 will crank but wont turn over. I changed fuel pump and filter, crank sensor, ETC sensor, starter, spark plugs are good. A few months ago we changed the ignition coil. Why wont this car start?


4 Things an Engine Needs in order to Run

  1. Spark
  2. Fuel – fuel pressure and fuel injector pulse
  3. Compression
  4. Timing – All of the above at the right time

Knowing the 4 things an engine needs in order to run lets us know what to look for. Or better yet look for whats missing. If you know you have spark you may try spraying starter fluid in the air filter. If the engine tries to run on the starter fluid you know the problem is fuel related. And now you can concentrate on the problem system. When the engine doesn’t want to start on starting fluid the next step would be to confirm no spark at the spark plugs.

Engine still won’t start

I have created a handy no start diagnostic chart for just such an occasion.

Check Engine Light On

Of course if the check engine light is on it would be a benefit to know why. For your vehicle though a scan tool will be needed.