Car ran very hot now doesn't why
 

Just got my car back last week after having new thermostat and radiator in. Second time driving today. Car ran very hot while I was out for lunch needle all the way right ac stopped working too. Happens right befor pulling into work parking lot. I figured low coolant not the case it was all filled up. Drove home after work needle stayed right in the middle.

My thinking maybe thermostat stuck then unstuck when cool? I really can not think of anything else. Any suggestions what to check.

didnt burp the system?

This happens to me every once in a while after I change the coolant, it's just air pockets that haven't been properly purged. I generally pull over at the first hint of a above normal temp, wait a few minutes, and open the radiator cap.

Good call will do that just to make sure. Check simple things first.

Tried to burp her. No air bubbles. Took her for a drive temp stayed normal. Will keep an eye on it.

Yeah you may have gotten rid of the only air bubble when it cooled after over heating.

Seems like that happens everytime I've drained the coolant. After it's warmed up the first time and allowed to cool it's always been fine.

Looks like my luck did not change ... it got hot again today. Odd it takes like thirty minutes. Then just sits at 80% hot. But not boiling into over flow. Going to get Ir temp gauge and check the temps. Maybe it's bad reading. Or half stuck thermostat.

Have you checked the oil, or had a coolant test done?

Most likely just a local boil or bubble.

My car does that every once in a while. Especially when I first start in the morning pull off to work by the time I get on the highway it gets up to 3/4s and goes back to the middle, its weird!

Umm tons of issues. First off boiled my thermostat and would not open until around 220. I got a new thermostat boiled it and opened up at 195 so that helped. Still got hot after driving for after about ten minutes.. And even hot while moving. Usually moving would help move air over the radiator. My fans polarity was wrong blowing into the radiator instead of pulling air through it. Then realized the top clips on both fan were not put on. That caused the fans to not be flush with the radiator so had to fix that. Embarrassed that all those things were messed up.

Sounds like you had a really good radiator shop work on the car.

Eunos, I think your issue is the thermostat bypass line. Make sure it's clear.

I have determined that every shop in the word half asses most things. It was not a radiator shop it was york automotive in Maryland. up until this point i was happy with their service. I was happy enough to actually have the car towed the 150 miles to get the work done.

In the past I have done most the work myself but lately have not had the time and some health issues have prevented me from doing it. just frustrating when you get something back and have to fix it again.

The thermostat I can kind of look past. the fans blowing the wrong way was a 5 second fix that they should have noticed. and should have finished the jobs by attaching the fans better.

Oh well it is over and now just going to focus on driving the car and enjoying it. in the 12 months i have owned it it has been street able for 3 months. I think the next thing that goes wrong with it will be the last for me. The miata is such a love hate relationship. I love it when it is running. It is so fun to drive. When it is not running I want to push it into a lake.

Do you have aftermarket fans? Trying to figure out how one could reverse the polarity with oem fans.

Yes they are aftermarket fans. Very easy fix. just flipped the wires.

Hmmmm. My experience with the Miata has been the complete opposite. Utterly reliable and easily maintained. Of course, I ran NA for many years before going turbo, but even turbo'd it's been great.

Probably the only thing in the current stable on par or better than the Miata is our Expedition. Indestructible.

Miatas are great and reliable. This is my 3rd. This project is just getting the best of me. Broken turbo, broken ball joint, had a kid so no time to work on the car. It will all get worked out. I have no choice now.. to much money into it to give up haha.