Ok, after following the Techboy soap opera with his engine to try solving a nasty heating problem ("http://www.dsmtalk.com/forums/show...ww.dsmtalk.com/forums/showthread.php?t=250522, here I am with the very same problem. But since I cannot afford to open my engine up to have my head checked/serviced yet, I'm taking the 'cheap' road and started checking the most obvious things and replacing cheaper parts first.
Here's what I did so far: I did a major radiator clean up, replaced the old water/fluid mixture, making sure that there were no air bubbles in the system, did a pressure test to check for leakage and it revealed one weak spot in one of the hoses so this hose was replaced with a new one, replaced both thermostat valve and pressure cap with OEM quality Mitsubishi parts taken from JNZtuning (stock parts, my car is 100% stock), checked the radiator fan and it's turning on when the coolant temp reaches 190F, the radiator fan is blowing in the correct direction (I did the piece of paper test and it was being sucked when I put it in front of the car while the fan is blowing the engine, so the air is flowing through the radiator as it should).
And here are the points where I think the problem can be, since these previous actions didn't solve the overheating problem:
- My water pump was replaced 3 years ago, but it's an aftermarket part and I don't even know the name of the manufacturer, so I know nothing about its quality. I don't hear any strange sounds coming out of it so I guess it's operating, but I don't know if it's flowing the required amount of coolant through the system or not. Since it's a belt-driven pump, the flow increases with the car's RPM. But when I increase the RPMs, the car gets hot faster!
- both coolant temperature sensor (that sends info to the ECU) and the gauge temperature sensor are very old and were never replaced by myself. My mechanic did some tests on it and it seems that the coolant temp sensor has wrong readings (it's sending lower temperature readings to the ECU). I did a clen up at the gauge sender sensor and It's giving different readings at the gauge now, it seems to be more precise than before. But I'll replace both of them ASAP with new OEM parts as well.
- Since my engine is operating at an average temperature of 278F (YEAH...WAY TOO HOT I know) for quite some time, I guess that my headgasket is gone!). My car warms up way too fast (It takes only 5-6 minutes in the morning to heat up! And every time I accelerate at moderate uphills, it starts heating up quite fast. I've read all the HG testing procedures that I could find, but none of them are actually ocurring in my case. No air is leaking through the combustion chamber in the water system, no water in the oil and no coolant loss being burned in the combustion chamber. The only clue I have that would point a finger to the HG is the faster warming up. The head has stock measures and has never been serviced before. When I had the engine opened up in nov/2011, my mechanic did a head measurement and it was flat plain, so we didn't take it to a machine shop to have it serviced. We then replaced the headgasket with an OEM Mitsubishi headgasket and that's all.
Clues? Thoughts? Tips? What would you do first in this situation?
Here's what I did so far: I did a major radiator clean up, replaced the old water/fluid mixture, making sure that there were no air bubbles in the system, did a pressure test to check for leakage and it revealed one weak spot in one of the hoses so this hose was replaced with a new one, replaced both thermostat valve and pressure cap with OEM quality Mitsubishi parts taken from JNZtuning (stock parts, my car is 100% stock), checked the radiator fan and it's turning on when the coolant temp reaches 190F, the radiator fan is blowing in the correct direction (I did the piece of paper test and it was being sucked when I put it in front of the car while the fan is blowing the engine, so the air is flowing through the radiator as it should).
And here are the points where I think the problem can be, since these previous actions didn't solve the overheating problem:
- My water pump was replaced 3 years ago, but it's an aftermarket part and I don't even know the name of the manufacturer, so I know nothing about its quality. I don't hear any strange sounds coming out of it so I guess it's operating, but I don't know if it's flowing the required amount of coolant through the system or not. Since it's a belt-driven pump, the flow increases with the car's RPM. But when I increase the RPMs, the car gets hot faster!
- both coolant temperature sensor (that sends info to the ECU) and the gauge temperature sensor are very old and were never replaced by myself. My mechanic did some tests on it and it seems that the coolant temp sensor has wrong readings (it's sending lower temperature readings to the ECU). I did a clen up at the gauge sender sensor and It's giving different readings at the gauge now, it seems to be more precise than before. But I'll replace both of them ASAP with new OEM parts as well.
- Since my engine is operating at an average temperature of 278F (YEAH...WAY TOO HOT I know) for quite some time, I guess that my headgasket is gone!). My car warms up way too fast (It takes only 5-6 minutes in the morning to heat up! And every time I accelerate at moderate uphills, it starts heating up quite fast. I've read all the HG testing procedures that I could find, but none of them are actually ocurring in my case. No air is leaking through the combustion chamber in the water system, no water in the oil and no coolant loss being burned in the combustion chamber. The only clue I have that would point a finger to the HG is the faster warming up. The head has stock measures and has never been serviced before. When I had the engine opened up in nov/2011, my mechanic did a head measurement and it was flat plain, so we didn't take it to a machine shop to have it serviced. We then replaced the headgasket with an OEM Mitsubishi headgasket and that's all.
Clues? Thoughts? Tips? What would you do first in this situation?