Fantastic week I've had.

Thursday the car suddenly started overheating. Yellow temp symbol came on, then red. UH OH. I checked my coolant tank and it was bone dry. Filled it up and went on my way to a friend's. Temp light went away. On my way back, temp light came on again. NO WAY! Managed to get it all the way to the house and it smelled funny. Hit red as well. OK. Fill it up again.

I am on my way somewhere else and the darn thing happens again. Fill it up with fluid. Happens again. Hits red, so I start to exit. THEN the exhaust light comes on. I feel like the car has suddenly lost some power. I fill up the reservoir and it goes away, but the exhaust symbol stays. Check for leaks, and don't see any.

So, I set an appointment for Monday. On Saturday, I get antsy and decide to go ahead and drop it off since a loaner won't be available anyways (we had a hail storm recently). On my way to the dealership via backroads to avoid high engine temps, I get some gas. Turn the car back on, and NO CEL or temp warnings the whole way there. URG.

They check the thermostat and bingo. $125 fee for diagnostic. So, instead of paying them to replace the thermostat I replace it myself with my father. Bled the air. Checked the coolant and it didn't move. Turn on and idle for 20 minutes with heater on. Still no movement. However, I immediately got a CEL and it still feels underpowered. Run to O'Reilly's and code P0118 is coming up. Engine Coolant Temperature Circuit High Input.

Check all my hoses and wiring after disassembling again, and everything is fine. Temperature sensor? But why does the car still feel underpowered? EVEN when just started? Like the turbo was turned off, though I can still hear it.

My dad thinks it might be the catalytic converter from the get go, but wouldn't that be firing a code?

 

With as many times you overheated it, I suspect you damaged temp sending unit and unit is still sending overheat info to ECU. But before buying a sending unit try resetting/clearing the fault code (at O'Reilly or Autozone, etc...) See if that clears up "limp mode".

 

It's not unlikely. It happened once there and on the way back. Thought it might have leaked so didn't think it would happen again. Filled up at the house, took off, and it happened again. Only hit red three times.

I checked AutoZone and they can't reset it. Only a dealership/repair shop for "legal reasons". Yay!

 

Just find someone with and OBII scanner and clear codes. That's lame that your Autozone won't do it. You can always buy one, they're not that expensive.

 

If i were in that situation, I'll check if the temp gauge is reading properly. I'd suggest you to replace the car thermostat and make sure that the system is fully bled.