I did something stupid and I learned and I am looking for help not criticism.
Ok here goes:

So 2 nights ago (Monday) I was parked at my house and I revved my car slowly to about 1-1.5 rpm (don't know why, Im weird) and then the check engine light came on. Always took care of the car. All maintenance was taken care of with the best parts. Anyway, I drive it carefully the next day (engine sounds fine, everything ran good) and I went to pep boys to get the code read but they're guy left so I bought some oil thinking maybe its my engine oil level. I unplugged the battery to see in the check engine light would come on again and while it was unplugged I let the car cool down (few hours) and checked all the oil levels and they were fine and then I checked the coolant reserve tank and that was empty so I filled that up with Green 50/50 coolant. I tried to open the radiator cap to see the coolant level and color of the coolant but it wouldn't come off so I gave up on that because it was late, i was tired, lazy, and stupid. So I just plugged the battery back and started the car for a few seconds maybe a minute and turned it off (no check engine light). So the next morning before I went to school I decided that it wasn't worth my engine overheating so I stopped being lazy and finally took the cap off. I had orange coolant in the radiator and green coolant in the reserve tank. I flushed out the reserve tank and cleaned up a little green coolant around the radiator cap/washer. When I turned on the car I noticed it idled a little lower than usual but I drove to school thinking the ecu just needed to adjust. I came to a stop and my car almost stalled! Got to around 200 rpm and went back up! I have a GS4 btw. It has been having a weird idle ever since this morning. I plan on doing a complete coolant flush, cleaning the maf, throttle body, intake, and idle air control valve.

Questions:
Can the little amount of coolant that mixed cause that problem or could it have mixed at all?
How long does it take for the two coolants to for a gel type substance?
Where and how do I get to my idle air control valve?
Any other reason why my car could be doing this? (back o2 sensors, exhaust leak, etc??)
Thanks in advance.

 

Have you lost any coolant at all since you filled it back up? Unless you have a coolant leak somewhere then chances are your head gasket is blown because unless the coolant is leaking from a hose or the reservoir or radiator there is no other place it could have gone except past the head gasket and the orange colored coolant in the radiator could be the result of exhaust gases mixing with the coolant (looked just like that on my subaru legacy when the head gasket went out) or just corrosion from not being changed regularly. I'd suggest taking it to a shop to have them test the coolant to check for exhaust gases at the very least to be on the safe side.

 

toyota coolant is red in color
orange could be from mixing with green (and i dont think that toyota coolant and green coolant after mixing together gona form any gel)

 

Don't think mixing coolant is gonna cuase a stall. You mentioned a check engine light. I think that code could have told you whats causing your stall issue. Check for pending codes in the system. I would also still do a coolant flush, but really don't think its a coolant issue. Good luck and hope it gets solved.

 

Should have waited to get the CEL but that point is moot. This is assuming you check your fluid levels often. Your coolant must be going somewhere. Any visible leaks? It's possible your water pump or radiator is leaking a small amount and burning off/evaporating before it makes itself known. If your head gasket is leaking your oil will show it.. How is your temperature? Sounds like the fluids never mixed. When the engine is hot enough it should push fluid into the reservoir..

 

I don't think I hav a leak. I replaced my radiator about a year ago and I think I just didn't fill the reserve tank but the radiator was full. Nothing missing. All my fluids were good. The check engine light hasn't come on yet but if it does I'm going to get it checked. Anything else that could cause my car to nearly stall?

 

I'd be insanely shocked if you had a blown head gasket. Honestly just sounds like a bad/unplugged/dirty MAF.

 

I am going to clean everything this weekend. hopefully it fixes it. CRC is a good brand?

 

1. Toyota coolant is red, but looks orange when it gets old.
2. A small amount of green mixed in won't hurt anything......but it's really just a good idea to go ahead and do a coolant flush using TOYOTA COOLANT.
3. empty reservoir is not scary. it's not a sealed system. it will loose coolant over time.....and can easily become empty if the level is not checked.
4.If your radiator cap was not replaced with radiator, replace it with the factory cap.

5. I don't think your running issue has anything to do with the coolant thing. if your idle gets low with a/c on in drive, the code may have been p0505. i think cleaning the things you said sounds like a good plan. especially the throttle body.

 

So I cleaned everything and no more stalling and no check engine light but now I feel a really bad shake when I turn off the car and sometimes the car shakes when I turn it on when its cold. Any preferences I appreciate the replies.