The ignition system or the fuel management system is most likely at fault.
Otherwise you might have a dirty/clogged Idle Air Control Valve, IACV, or Fast Idle ThermoValve, FIT, which ar located on the intake near the throttle body. You can try to clean them. They gerally have coolant lines running through them as they sense coolant temperature to change the air/fuel ratio by either changin the signal for throttle position to the computer or actually moving the butterfly valve, or they have ports to let in air to lean otu the mixture, this is usually used with the FIT vavle like a choke would work. So, you would have to drain the coolant, remove the parts and clean them with brake cleaner and maybe some small pipe cleaning brushes. You must be very careful with the IACV especially as any damage to the diaphragm will cause it to no longer funstion. If you find the diaphragm is already damaged, the IACV needs to be replaced and might be the problem.
Clean the ports in the direction of airflow, menaing from the outside going towards the intake as doing the oppsoite may clog the ports further.
Since there is also the possibility of an electrical issue I am including a link to a walk through diagnosis for stalling issues.
My first sugesstion though, would be to get the trouble codes pulled from the OBD II port. Any Advance Auto or Auto Zone will do this for free and it will generally make the diagnosis process a great deal easier. The other suggestion is to check the fuel pressure with a mechanical gauge, which the aforementioned auto parts sotre have on a loaner program basis, and check the pressure manually.
There is a test port on the fuel rail and I have included a chart of what the pressure should be.
Here is the link to the walk through;
Let me know if you need any more help or have any questions.
Saturday, October 22nd, 2011 AT 2:09 AM