Temporarily stranded...again

[lastchance]

2003 Vue, 6 cylinder, with 140K miles. Recently car has started to die after running for 45 minutes or so. Once hot the only way to start is with starter fluid. Once it cools down it will start fine and run until getting hot and then dies again. Check engine light is on and will take it in to have codes checked. Any simple things I could check on my own? O2 sensor? Seems after reading this forum the CPS is a likely culprit. Any way I can change out myself? or if not, what is approx. charge to have this replaced? Also I believe that the fuel filter is original and will change out today. Any chance this might be the problem and, if so, what would be the difference in fuel delivery to the engine when hot vs. cold. Thank you:dizzy:

[fdryer]

Your Vue was long overdue for the fuel filter and not likely the reason for the engine dying out when warm. Its also not likely the cps as the engine runs, even after re-starting with starter fluid. An intermitternt cps will simply kill the engine from running and no amount of starter fluid is going to bring life back to the engine. The typical intermittent cps failure occurs when the engine is running and needs to have the engine cool down before working again only to heat up and fail at random somewhere down the road. The fact that you're able to use starting fluid to start the engine is pointing somewhere else but not to the cps. If you're sure that starting fluid doesn't get the engine to start then it would be the cps.

The best thing to do is to retrieve the SES codes, from your favorite auto store that can read codes for free or pay Saturn to do this. The code(s) can possibly point the way. Be sure to write down the codes so you can find out what they mean and/or post them for more assistance. The code list is in the How-to library on page 5 titled OBD II Powertrain Codes. You'll find that the cps isn't cheap but for information purposes its located next to the oil filter and mounted with one bolt. Check the online prices at http://rockauto.com or http://saturnparts.net. Saturn will charge much more to diagnose and replace any parts than if you did this yourself. Spark plugs changed yet? They were due at the 100,000 mile interval along with the timing belt and water pump. The last two are very difficult to DIY unless you're totally familiar with timing mistakes and can correct for it while replacing the timing belt with or without the right tools. The spark plugs are more difficult to replace than usual due to removal of 2/3rds of the intake manifold runners and ignition modules before seeing where the spark plugs are hiding.

A fuel pump will always output more pressure than the engine requires and the fuel pressure regulator maintains pressures with no regard to engine temperatures. A constant fuel pressure is absolutely needed in order for the emissions control program to operate in the narrow emissions band and for the EFI system to operate correctly otherwise the O2 sensor will run ragged trying to compensate for rich/lean conditions outside its designed parameters.