Why does a car not start when it has fuel and spark?
If the mixture is too weak then there isnt enough of a bang in the cylinder to provide the power for the engine to turn. If too strong there isnt enough oxygen and the fuel isnt burnt (it will usually run with a choking belch of black soot and will stop at some point as the plugs become too mucked up).
What do you need to know about engine will not start?
All engines require three things to start and run; spark, fuel and compression. So, if any one of these is missing, your engine will not start. With a engine will not start issue, the possible causes are plenty; so it’s important to understand, what it takes to make a engine start and run.
What causes the fuel pump to not start?
The fuel pump is running and delivering normal pressure to the engine But, with all that working your engine still will not start. So, the most likely cause, is that the fuel injectors are probably not opening. The (PCM) uses the trigger signal from the crankshaft position sensor; and/or camshaft position sensor to pulse the injectors.
What happens if you spark the engine at the wrong time?
But these things generally have to occur at a specific time. If you spark on the exhaust stroke then nothing will happen. Assuming it is a fuel injected engine, if the fuel is injected at the wrong time it will cause manifold wetting, and potentially icing, but also a poor running engine or a no start condition.
What makes an engine not start or run?
All engines require three things to start and run: spark, fuel and compression. If any one of these is missing, your engine will not start. The fuel pump is running and delivering normal pressure to the engine
Why is my car engine not getting spark?
There are lots of reasons why you might not be getting spark. If it’s an old car, it might be your points. If it’s an old motorcycle, it could be your ignitor. You could also have a bad distributor, a bad coil pack, or even bad crankshaft and camshaft position sensors.
What to do if your gas engine won’t start?
Do not do anything else if there was no spark, as the trouble is inside the internal workings of the engine and requires professional repair and tools. Keep open flames and heaters away from the work area. David Machado has written technical and home improvement articles since 2008.
Why does my lawn mower not have gas and spark?
Three critical elements combine in a lawn mower small engine to allow it to start and run. If the lawn mower has spark and gas it’s still missing the crucial air element. Air mixes with the fuel for better combustion and it also keeps the engine cool enough for continued combustion. If the lawn mower has spark and gas, check the air supply.