Here's a chronological order of what my cars been doing:

-While downshifting on a left turn engine turns off and CEL turns on.

-Car won't start up, I think it "turns" but doesn't start.

-24 hrs later, Car starts up and I drive it 1 mile home. Won't start back up again unless I leave it for a while (it still "turns").

-I notice my coolant reservoir is nearly empty, I fill it with 50/50 water and some Royal Purple Coolant Additive.

-I DONT DRIVE MY CAR, I return to look at my coolant reservoir to find it empty again!

-I fill the reservoir with water to get me to O'Reillys, the reservoir is empty by the time I get there (only 3-5 miles away).

-I get codes P0116, P0117, and P1410

-Refill with water to get me home (they had no antifreeze)

*sometimes engine revs on its own
*sometimes engine turns off in the middle of a drive without overheating
*heater isnt as warm, and takes a long time for it to get warm

-Car has a hard time starting, but starts as long as engine isn't overheated.


What's wrong, and how do I fix it? I checked the reservoir and there are no leaks in it, yet it acts as if there is. Help please!

 

Is your radiator leaking? Water pump? Hoses, both radiator hoses or hoses on the intake manifold? Heater hoses? Is it wet inside the passenger part of the foot well?

No head gasket leak?

 

NICE! I think you're on the money! I've been fiddling with the car all day today and I'm pretty sure the problem is a leak. I'm just not sure where it is, though I think its coming from the radiator. I find some liquid seeping onto my front bumper so I make that assumption. I will look for some DIY radiator leak fixes or replacements, if you have any other advice I'd really appreciate that too! Also thanks for the comment!

 

confirm that it is indeed the radiator. My advice is Koyo Rad. Bite the bullet and get a nice one. The last thing you want is an overheating engine.

 

Sticking in a new radiator is very easy to do. Verify that it's leaking first and not a hose, or some other part. It could be something as simple as replacing the cap.