Possible Bad Headgasket?

[LxiMax]

In need of opinions... I've seen this before on cars and it's normally turned out that the car has had a bad headgasket. The temperature gauge goes to the midddle but it rests right below the middle. Is this normal for this type of car? Car is a 95 GST.

 

[russ96gst]

Yes that is the perfect spot, dont understand how that could indicate a bad headgasket, never heard that one before.

 

[buhay6]

If it was a bad head gasket you'd either see a white creamy oil at the end of your dip stick OR you'll have coolant running down from your head. My Supra's head gasket went so I could take a pic to show you exactly what a bad head gasket looks like. (littlerly my exhaust manifold gasket is soaked in coolant) just glad there's no coolant in my oil ### it had a fresh oil change a couple days before she blew! saved myself 50 bucks! w00t w00t!

 

[Morris]

You can have a blown headgasket without coolant in your oil. It can break and have only the coolant enter the cylinders, you will see white smoke come out of the exhaust.

 

[jimbob_843]

The temperature rises until it reaches the thermostats opening point which is 180*. Then the thermostat opens to allow better flow and thus slightly lowering the operating temperature.

 

[russ96gst]

^^^yes these are both true, yet still a temp gauge showing slightly below the middle has never been a sign of a blown headgasket to my knowledge.

 

[jimbob_843]

Nope me either, a bad hg can have many symptoms but this sir is not one.

 

[buhay6]

You can have a blown headgasket without coolant in your oil. It can break and have only the coolant enter the cylinders, you will see white smoke come out of the exhaust.

wow cant believe I forgot to add that! ya your exhaust could be white as well indicating your burning coolant. thanx for the add there Morris.

 

[Abe'sGST]

another symptom would be bubbles in your coolant reservoir...if your gauge is working properly, i would go for either the ECT sensor or your thermostat may be bad, it could be stuck open and not letting your coolant get to normal temperature

 

[codeofdastreets]

If you compression test the motor and it has a bad hg it should bubble the coolent, correct me if im wrong.

 

[linen88]

If its blown between the coolant and pistons yes, take all the plugs out if doing compression test to makes sure its not blown between cylnders too. This doesnt sound like a blown hg tho, check both upper and lower radiator hoses to see if there both hot and the thermostat is opening and be sure its topped off with coolant.

 

[Pwrtrip75]

In need of opinions... I've seen this before on cars and it's normally turned out that the car has had a bad headgasket. The temperature gauge goes to the midddle but it rests right below the middle. Is this normal for this type of car? Car is a 95 GST.

If thats all is your concern....nothing is the matter. If you are concerned it is not warm enough... its winter. If you're concerned its too hot... its not.

 

[bskills]

Hi Guys, I removed my thermostat to avoid the possibility of it sticking. Are there any drawbacks to that?

 

[nek]

Hi Guys, I removed my thermostat to avoid the possibility of it sticking. Are there any drawbacks to that?

Car will take longer to heat up if at all.
Its not good for your engine to run lower then operating temperature.

 

[Pwrtrip75]

Hi Guys, I removed my thermostat to avoid the possibility of it sticking. Are there any drawbacks to that?

The common misconception people have is that the thermostat regulates how hot the engine gets.. No. It regulates how cold it runs.

 

[LiquidX]

Hi Guys, I removed my thermostat to avoid the possibility of it sticking. Are there any drawbacks to that?

Yes, see below

Car will take longer to heat up if at all.
Its not good for your engine to run lower then operating temperature.

I'll elaborate on these items. The car will heat up, some more than others which is purely based on the cooling system efficiency.

The ECU needs to see a temperature reading of 180* to enter 'learn mode'. Running too cold of a temperature will increase wear on the motor. Not reaching a minimum of 200* can also prevent condensation in the block from evaporating out.

Not having a thermostat in some cases can cause over heating as well due to the coolant not having enough time in the radiator to exchange heat. A somewhat fix is to use a gutted thermostat to allow resistance where the thermostat sits.

The common misconception people have is that the thermostat regulates how hot the engine gets.. No. It regulates how cold it runs.

The thermostat just designates when the coolant can circulate from the block to the radiator. The radiator and cooling system efficiency determines how cold it will run.

 

[stuckwithgsx]

Yes, see below


I'll elaborate on these items. The car will heat up, some more than others which is purely based on the cooling system efficiency.

The ECU needs to see a temperature reading of 180* to enter 'learn mode'. Running too cold of a temperature will increase wear on the motor. Not reaching a minimum of 200* can also prevent condensation in the block from evaporating out.

Not having a thermostat in some cases can cause over heating as well due to the coolant not having enough time in the radiator to exchange heat. A somewhat fix is to use a gutted thermostat to allow resistance where the thermostat sits.



The thermostat just designates when the coolant can circulate from the block to the radiator. The radiator and cooling system efficiency determines how cold it will run.

I was going to add the bolded text in here and the other thread regarding this. I've gotten cars that will only overheat while idling and not while driving. Took me a while to figure out that driving the car allows more air to go through the radiator making temps colder, but just sitting there it gets heat soaked and overheated (the fans aren't that amazing haha).

 

[Pwrtrip75]

Yes, see below


I'll elaborate on these items. The car will heat up, some more than others which is purely based on the cooling system efficiency.

The ECU needs to see a temperature reading of 180* to enter 'learn mode'. Running too cold of a temperature will increase wear on the motor. Not reaching a minimum of 200* can also prevent condensation in the block from evaporating out.

Not having a thermostat in some cases can cause over heating as well due to the coolant not having enough time in the radiator to exchange heat. A somewhat fix is to use a gutted thermostat to allow resistance where the thermostat sits.



The thermostat just designates when the coolant can circulate from the block to the radiator. The radiator and cooling system efficiency determines how cold it will run.

If the system is pretty balanced then it would stay at the operating temp it was designed to....Unless operating conditions play a factor.....Weather, or the engine.

Also if its not heating up it could be related to something else also... Something causing it to run a little more rich and the engine will run cooler, colder weather making the radiator work better also, cooler air, and cooler fluid to cool... a combination of things that could all be cause by something so simple as a temp sensor that is faulty. I dont know this exact vehicle operating system, but if the computer thinks the engine is cooler than it is.... does it richen the A/F until its reached a certain temp? This will make a car run cold in the winter, and wont set off any codes because it doesnt think anything is wrong... its just cold and hasnt warmed up to op temp yet.

I guess we'll never know...... The OP never replied to anything.. We dont even know what or if there is a problem and we got diagnosis..... Oh well, another post count for me.

 

[rEclipserGST]

1. Thermostat (can boil yours in water to see if it works correctly)
2. Radiator cap
3. Coolant hoses (some can dry rot or have pinholes in them)
4. Overflow bottle filled up (sometimes they leak)
5. Coolant temp sensor (if faulty, can cause hard cold starts)
6. Waterpump
7. Headgasket (compression test can tell you a lot)

I would check in the order of those first. They get harder as you progress. Easy ones are cheap. Your radiator could have a leak in it as well, mine did at the top where the plastic & aluminum meet.

I would do a compression test /leakdown test. Pressure test the coolant system. This all should point you in the right direction.

 

[LxiMax]

There's really no issue I can see ... I've logged it as maxing out around 215 at a long idle then the fans kick on and it drops back down. The only reason I mentioned something about it being a possible HG is b/c my Subie died and it's temp read in the same area since we bought it. Then again, we didn't find out until it blew up that there was no t-stat in it.