Chrysler Repair: Pt Cruiser idle problems, advance auto parts, vacuum lines

Question
Hello, I was wondering something about a '04 Pt cruiser that I have, it seems just recently, like within about maybe 2-3 weeks time, that it started to have problems starting, and staying started, like when I go to put it in gear and apply gas the engine sputters and shakes and then sometimes dies. There is said sputtering when it solely idles, it will also do this even when it is driving at times. I can also notice when I turn it on sometimes that the starting up of the engine is shaky and sputters badly. An advance auto employee, while running a diagnostics saw the engine just sort of jump up (aka the odd sputtering and shakiness) while the hood was up. I also have ran numerous types of checks, such as going to advance auto parts and getting them to test for a computer error code, and I have ran a Computer system code check by turning the key on off on off on, and all it said was done. I have replaced the battery, checked for corrosion and cleaned the cables running to the battery to be sure. I also went ahead and changed the spark plugs. People I know have suggested maybe something wrong with the O2 sensor, the fuel filter and/or pump, catillac converter, and me, myself, I aim to think possibly something to due with maybe changing the transmission fluid, or oil might help? But I think there is a more serious problem occurring here. If you could help me that would be greatly appreciated.

Answer
Hi Nick,
Take a look at the egr valve if there is one. (Look on the underhood sticker that shows all the vacuum lines and see if an egr is shown there or not; I don't have a manual that is so new as to be sure). If there is one, located the valve stem between the round top of the valve and the valve body proper, hidden in the flange area between those two parts. There would be a slot in valve stem which you can move via the tip of a screwdriver and you can test to see if the internal spring action causes it to close to a dead stop. If not, then spray some WD-40 on the stem where it enters the valve body and work the stem back and forth.
Other than that, check over the vacuum lines connected to the intake manifold (use the sticker as a 'road map') to be sure none are detached or cracked.
When you write back let me know which engine you have.

Roland