What's wrong with my car? Can someone help to shine some light on the subject? Thanks for reading.?

Some basic info first: 2005 Nissan Sentra 1.8 S/1.8 Liter

80,000 miles. Live in South Florida (it it matters).



The engine won't cool. When I am driving slow or in idle I see it move to the exterme high (hot) end. Then it comes back down to normal. Up and down.

I was driving on the interstate today the temp gague went to high and the engine lost power. First it bucked a little causing the check engine light to come on. It didn't stall, but was close to it.

I believe the problem is somewhere in the cooling system.



If you care I will give a little more detail:

A brief history, it may help to understand the point I am trying to make. About 8 months ago or so I began noticing the A/C wasn't cooling all of the time as it should. It was blowing almost warm air. It wasn't as cold as it should have been.

About 4 months things started happening. The temp. gauge started to go up as the engine was getting hot. It got very high, so I pulled over and waited for it cool down some. The coolant in the reserve tank was boiling. I did this about 4 times (Each time the coolant was boiling) trying to get home. About 10 minutes later I was driving and things looked ok then it got hot again and the engine buck a little causing the check engine to come on. At that time the car lost power. It didn't stall, just lost power. I pressed on the gas and nothing. I notice the RPM was flicking between 2K and 3K. I pulled over turned off the car for a few minutes. Afterwards it started up and ran fine. By the time I got home the engine lost power 2 times-each time I had to pull over and wait. All of the time I pulled over the coolant in the reserve was boiling and of course the temp gauge was hot.

When I made it home I waited until it cool down. There was no coolant in the radiator. It was bone dry. There weren't any leaks anywhere and never was. Nothing was sprayed on to the engine. The reserve tank was in between the min a max line. I filled the radiator with coolant. Afterwards it was fine. It wasn't getting hot anymore. My AC was even working fine after that. It's blowing cold air like it should.

About 2 months ago I was driving and the temp gage started moving again. I was at a red light and the high pressure (top radiator hose) hose popped off. I was able to put it back on and the coolant in the reserve tank started to boil again. But now the reserve tank is over the max line. The radiator was dry again. I put in more coolant and like the last time it seemed to had fix the problem. Still no leaks. A week after that the temp gage goes up and down. It goes high in idle or slow driving, back down at normal speeds. Sometimes the AC becomes warm when the temp goes up.

3 weeks ago I got the raditor and cooling system flushed by professionals. The next couple of days nothing was going on with the temp. After 3 of 4 days it started up again---up and down goes the temp gage. About 2 weeks ago, after experience some of the same problems the engine almost stalled out. I turned off the car and restarted it and it ran fine. After it cooled for awhile the top radiator pressure hose was flatten- squezzed together. That happened once. Even since that time it appears to be normal.



For the past month: After I turn off the car I can hear coolant in the high pressure (top of radiator) hose trying to escape. It is a bubbling type sound in the hose. The coolant in the reserve tank smokes when the lid is taken off, but it isn't boling liked it did. Also, it is above the max line. After awhile the coolant will go below the min line. The hotter it is outside the more problems it'll have.



P.S.-- The check engine light usually goes off by itself after 3 days or up to a week. When the engine gets high and bucks the light comes back on.



I was thinking about getting a new hose and changing the thermostat. What can be the problem? Thanks again for reading.
What's wrong with my car? Can someone help to shine some light on the subject? Thanks for reading.?
The thermostat would have been the first thing I would have replaced at the very first sign of overheating. It's a lot cheaper than replacing an engine.



First you need to do a compression check. This is necessary to make sure you still have a good engine.

Then do a cooling system pressure check.

Then if those two check out, replace the thermostat and radiator hoses.

Refill the coolant using the proper fill procedure to eliminate air bubbles in the system and do a pressure check.



One more thing.

Check the fan.
What's wrong with my car? Can someone help to shine some light on the subject? Thanks for reading.?
Well, that means that something is punctured and your coolant is leaking out. I wouldn't be able to tell from here, but you should take it to the shop as soon as possible and get the part replaced. Don't simply try to patch it up, because if you do, it'd only be temporary. Did you try adding more coolant in there? See any leaks?



It could be the hose, or it could be the radiator. See if you can see any signs on a leakage or previous leakage when you look under your hood.
u can only change thermostat and make sure cooling fan coming on check drive belts [if it drives water pump ] but i woul say you have blown the head gasket or cracked cylinder head because not rectified straight away when problem started [hope just thermostat but doubt it]
you hav eather a bad radiator notalowing enough coolant trew (not so likely) most likely is the water pump ac will have nothing to do with it overheating except when the ac is on ur engin runs just a lil hotter(ac condencer getting warm) but you need to start it up when its cold with the radiator cap off sit there n rev it up from 800 rps to 2 or 3000 rpms watch the water if you see it go up and down quick the pump is usually working somthing isnt alowing the proper amout of water to flow so try 1 or both of them parts
It sounds to me like your thermostat is severely stuck. It's a very easy thing to replace and they usually only run about $5. If that doesn't fix it, your water pump is blown out, in which case you need to get that replaced as soon as possible before you blow out your motor. A leaking cooling system would not cause the engine to overhead this bad. Have you checked to make sure that there is coolant in the system?
Watch this, I'm going to read your mind . . .



This is related to that squealing noise you're hearing sometimes after you start your car.



You've got a bad water pump and the coolant is leaking, actually it sounds more like running, out of the weeping hole.



The warm A/C is a common symptom of a car that's overheating. That brings me to my next point, STOP OVERHEATING YOUR ENGINE!!! It can, and will, cause permanent, irreversible engine damage. It wouldn't be uncommon at all to seize your entire engine as you drive it with the temp gauge in the red and that'd mean it's time for a new car. Next time your temp gauge gets near the red, pull over and turn off the engine immediately! The check engine light and the bucking and loss of power are all death throes, you were VERY close to ruining that engine over a $300 water pump repair. You've likely damaged your head gasket and possibly valve cover gasket due to the repeated overheating too.