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A malfunctioning AIC will definetly mess up the idle. An EGR valve stuck open or leaking will also cause low RPM problems. The TPS may or may not affect idle, depending on what it is trying to do. Being that it runs OK when cold, it is a good indication that the engine is mechanically sound, but running bad when hot could be a result of a bad sensor. Check the coolant and air intake sensors with a scanner and verify that they are reporting the correct temp. These sensors are prone to drift as they get older.

 

Fuel injector maybe? I sprayed one fuel injector and could almost stall the engine. Seems like it is sticking out half a inch from the whole.

 

First off, you're using Mobil 1. Big mistake! The oil is very thin and your engine is not made for full synthetic. I use 10W30 Castrol GTX and my car runs great! And, it's cheaper too come time to change the oil. The test results are in and guess what, there is no advantage to running synthetic oil on and older engine. None, zip, nada! New cars are different and so are cars with a freshly built engine from the gound up, and yes they will get better performance.

Now, as for the car shaking are you sure it's the engine? I had a 2-piece driveshaft that got out of balance and ended up shaking my car bad at idle. I also had 3 cracked fuel injectors that were causing an issue too. If the EGR is gone or going you'll get alot of black soot coming out of the engine. Run the car with the back facing a wall and hit the gas a couple of times to see if you're spraying soot out of the back. If that's all fine then you could have a bad timing chain.

 

If you have an injector sticking out, then it is probably allowing unmetered air to enter the intake, which will also cause bad idle. Try pushing it back in, but I suspect the reason it came out is because the "O" ring is bad, in which case you should replace the whole set of "O" rings..