Does This Make Sense To You? Please Help.
 

Car: 2008 Camry

Short Story: Back in October 2015 Toyota did engine work relating to their recall on engines that had excessive oil consumption. They said it involved taking the engine out, amongst other things. Fast forward to two weeks ago. While driving home the A/C suddenly stopped working. It blew warm air and the temp gauge dropped to 0 as if the engine were cold (even though it was still driving). It never showed signs of overheating, no warning lights or anything. After pulling over, upon inspection, there was no coolant in the radiator or reservoir. And now the car wouldn't start. Resulted in getting a tow.

The Verdict: The service rep. is telling me that the water pump went out which resulted in overheating (water pump was replaced about 2 years ago, thermostat in the last 6 months). This overheating then resulted in the warping of various engine parts. So basically I need a new engine.

Question: From the behavior I explained above, does it make sense that the water pump is to blame? What stumps me is that the temp. dropped to cold as opposed to showing overheating. The reason I'm questioning it is because if this was the result of an engine problem, it is covered by a 12/12 warranty from when they did the engine work last year. I'm just trying to verify the best I can that they aren't trying to pull a fast one on me to avoid blame for subpar engine work before I spend thousands on repairs.

Any help would be much appreciated. Currently I'm trying to keep it glued together as to not upset the wife.

If there is no coolant then the temp gauge can read stone cold. Air won't do much to register with the sensor. The water pump could be your culprit.
The only thing that is weird is that it seems like it the pump failed very abruptly. You usually slowly lose coolant and then when there is little enough to go round, you begin to notice the engine temperature rising.
There are many possibilities and it's hard to say without looking at it. They could have done a poor job on the repairs in the first place and gave you back your car with a leaky head gasket. A leaky head gasket can be hard to notice and leak over time.
Again, it's tough to say. I would not expect the stealership to own up to any mistake that they might have made.

Thank you. I got to thinking and may have caught them in a lie/mistake. When I brought the car in they had told me they could find no visible reasons as to why I had lost coolant and then asked for permission for the tear down to see if the coolant problem was somewhere inside the engine. After 8 days of waiting they call to tell me my water pump was the issue. I'd assume if someone brings in a car that can't hold coolant, they would check the water pump before saying they don't know what happened. Looks like I have a full day tomorrow for arguing with their service department, Toyota corporate, etc. Fun times!

Did the engine make any strange noises before the you stopped?

When was the last time you checked the coolant? It is possible the coolant was getting lower over time and finally reached this low point. Who changes your oil and when, most places check coolant as a routine.

Concur with Patonium on the rise and fall of the gauge if a massive leak.

It is possible for a water pump bearing to fail in such a way it takes out the seal to an extent water can flow out of the system at a good clip.

A competent mechanic can pressure test the system to simulate its operation when hot. If a bad pump caused a leak, coolant leakage at the pump should be evident.

I agree with Joey.
I have replaced the water pump in my '07 and the only indicator that it was bad was some pink residue around the pump itself, it is the shaft seal that went bad on mine.
Keep us posted and good luck. I think you are in for a fight.