Black Betty

iTrader: (60)

Again, did you check for proper thermostat operation?

Black Betty

iTrader: (60)

It's not expensive or particularly difficult. You could DIY.

daonlyillwiz

iTrader: (2)

Check the thermostat as mentioned above.


FYI, if you EVER over heated the engine to the point where the needle was past the 1/2way mark you could have possibly warped your cylinder head(s) thus trashing the head gasket and thats why you are experiencing these issues.

You're not consuming coolant or pushing coolant into the overflow bottle right?
One more thing you can check is a compression/leakdown test

ahmed.zakut

Well guys..today I visited the dealer as the workshop manager is a very close friend. I asked him to check the thermostat. .he replied that they've changed it when they replaced the radiator. :| ...then he opened the history of the car to show what they've replaced already. I was shocked..they've replaced everything related to the coolant system. Radiator,hoses,2 thermostat the front and back, coolant temperature sensor. So I said : I gave up ..they've checked the compression and it is fine..then we went together to Hyundai workshop to pick his car..as all of them also my close friends as my wife owns a Hyundai.. I was talking to the workshop supervisor in Hyundai that there is no solution or fix for my problem and I have to live with it..he asked me few questions about it.and baaaaam..he said it is exact story of a car which drove him crazy as it did the same thing..but he replaced everything in the cooling system then he replaced the head gaskets and the result were zero..he gave up for a while, start thinking about the report he will write to replace the whole car for the customer. .and then he realized that he didn't changed the radiator cap..!!??.. he said it was like magic..when he replaced the radiator cap the car ran fine..no more unstable temperature. .so he told me it is your last chance..and he was so sure that it will fix the problem..so I will replace it next week as it is very cheap and there will be no need to wait for the warranty approval..I will keep all of you posted.

ahmed.zakut

Well as you can see in the pics..it never ever touched the half..today I checked the coolant level my self it was fine..

Black Betty

iTrader: (60)

Damn. I didn't think of checking the radiator cap. It could actually be something that simple. I hope so. Good luck.

ahmed.zakut

Thanks a lot. .yup it could be that simple.. I realized that the engine cooling system could be the most complicated thing in any car..because you won't be able to solve the problem immediately. .it is a trial and error ..lets see what will happen when I change the cap.

Black Betty

iTrader: (60)

I know it seems like it when you're having trouble solving an issue, but the cooling system is actually one if the simplest systems on the car. Requires little maintenance and the only moving parts are the thermostat, water pump, and radiator cap.

ahmed.zakut

Well , Guys till today i did not replace the cap it was a busy week... Anyways.. Today when I parked my car as usual, it starts climbing above the 1st mark, i turned the heater on with the A/C button to allow the radiator fan to work...rev up 2 times..and baam.. Immediately went down where it should be.. !!! Any suggestions.. Or shall I replace the cap first and lets see what will happen..!!

ahmed.zakut

I checked the water pump and the thermostat
They are fine..but the thermostat starts opening when it reach the 1st mark. ..the radiator fan kicks when it's above the 1st mark..when I switch the ac on..it goes down to the 1st mark and stays there..the dealer still claiming that this is the normal operational temp..but how come if it goes down when I start moving on a high speed..and when I switch on the ac it goes down also..!!

HoldmyMouse

Do they have another vehicle on the lot to replicate this "normal" temp?

ahmed.zakut

Guys, they've changed the thermostat. .and I've seen the temp on consult..it is normal..so I start thinking about the instrument cluster. .today in the morning I've checked the temp gauge. .and I realized that when it is cold it is above the g25 which they gave me as a courtesy till they fix my car..then I realized that there is something going crazy in the gauges..for the RPM AND THE TEMP GAUGE. when I switch off the car and after a minute ..the gauges start playing up and down..I will share the link on YouTube when the upload finish.

ahmed.zakut

Finally. ..here is the link below..I know you will get bored watching it..but the purpose is to show the symptom and when the crazy thing happens. Check it 2 times ..1st your eyes will only catch the RPM. 2nd time you will see that the temp also moving..

Black Betty

iTrader: (60)

I've never seen anything like that. Weird. If you've have had them change every component in the cooling system that could be causing the issue and the consult shows normal operating temperature while the gauge reads high temperature, it stands to reason to me to try changing out the gauge to see if a new one displays the same temperature as the consult is reading.

ahmed.zakut

Thanks bro. I really appreciate your support ... a friend of mine explained me a theory about that..but he said definitely something wrong..he said those electrical throttles closes after a minute and you will hear the ticking of the relay. But this is something different. He said if it is only the RPM I would say it might be normal. But both RPM and temp. For sure something wrong..either the instrument or the ECM.