2001 Pontiac Sunfire will not start

mommyof05

I have a 2001 Pontiac Sunfire. I shut the car off and when i went to try to restart it it would not start. My cousin brought a computer checker thing and it would not read and the check engine light is not on. I put a new battery, spark plugs, plug wires, coolant sensor, new fuel filter and fuel pump, sometimes it will start for a few seconds then shut off on its own or when you try to give it fuel. They sprayed starting fluid in and it will run for a few seconds then shut off. Please help!!!!!!!!!!!

thecardoc3

Your post contradicts itself. If it starts and runs with starting fluid, then it can't be getting fuel because the starting fluid ended up being fuel as long as it was available. How much fuel pressure does the system have? Has anyone measured the on-time of the injectors? The right way to do that is with a low amps current probe and an oscilloscope. Many people try and use a noid light to see if they have injector command pulse and that has tricked them into thinking they had pulse when there was a circuit problem that prevented the injectors from actually delivering fuel.

You wrote that the Check Engine Light is not on. Are you sure about that? Key on, engine off (not cranking) the light should be ON. If it isn't then there is a basic computer problem like no power to it. If the light is actually on, does the PCM communicate to a scan tool? If so what codes (if any) are setting? Look at essential data pids for starting the engine. CTS (coolant temperature), MAP (manifold absolute pressure), RPM and TPS (throttle position sensor) Tell us what these data pids show.

thecardoc3

See the other response. With no CHECK ENGINE light, you need to check for powers and grounds for the PCM, and then test the 5V reference line for a 5v signal at any sensor that is easy to reach under hood. If you don't measure 5v there, what do you see? A high voltage suggests a loss of a ground circuit for the PCM.
A low voltage could be no power to the PCM, a grounded 5V reference signal or a bad PCM. You might have to disconnect ALL of the engine sensors to be sure that one of them hasn't shorted the 5v reference to ground.

mommyof05

I have a 2001 Pontiac Sunfire. I shut the car off and went I went to start it again it would not start. Check engine light is not on...short story...I changed battery, plugs, plug wires, fuel filter, fuel pump, changed oil & filter and changed the coolant sensor. It will sometimes (very rarely) start for 20 - 30 seconds and then shut off on its own or when you try to give it fuel. They sprayed starting fluid it and it will run for a few seconds. They told me its getting enough fuel and fire. Anyone have a clue what else to check?

mommyof05

The check engine light comes on when you turn the switch on, but when the car is running for the 20 or so seconds its not.

mommyof05

I have no idea what any of that stuff means? They just said it was getting the fuel pressure it was supposed to and 99% of the time it will crank over n over and will not start...but every once in a while it will run for 20 or 30 seconds and either quit on its own or quit when you press on the gas peddle. They said it will start right up and run when you keep spraying starting fluid in it. I can not afford a mechanic so my sons and I are trying to fix it.