Ok so my car started overheating lately, but has gotten worse. Will only overheat during a long period of WOT time and will go back to normal temp in 1 or 2 minutes. I just drove it 2 hours on the highway/local without passing 4k rpm and it didn't overheat at all. I've noticed that both hoses are hard after I drive it for a little while and sometimes the radiator spits antifreeze back in the reservor. Previous owner told me he put a autozone(felpro) headgasket and re-used stock gsr headstuds and tourque them down with a bootleg autozone tourqe wrench.

Could it be a crack sleeve, bad headgasket, etc?


NA ls/vtec b16pistons everything stock.
I've already tried...

New radiator
3 thermostat's
New hoses
Fan is always on
Bled the system for hours
OEM water pump is 10k miles old
Compression test. 225 all across
It's not mixing oil/antifreeze at all
No smoke

I'm lost?

 

Kinda sounds like you might have an air bubble somewhere. Try bleeding the coolant system see if that helps.

 

its probaly the head gasket but if nothing is mixing then i dont know if it would be the head gasket

 

Already bled the system for hours and still nothing. Lets say after a WOT run, i slowly remove the rad. cap(3rd new one) theres alottt of presure/air? coming out until i completly remove it. It's like air its getting in the system or something. Also water pump is 10k miles old.

 

Leakdown test

 

are you losing coolant? sounds like u either have a small leak in your system or your head gasket needs to be replaced. get a hold of a radiator pressure tester. not sure what its really called. You pump pressure into your system and the pressure shouldnt change over 5 min.

 

open up your radiator cap with the radiator filled to the top then start the car. if the coolant shoots up from the radiator then most likely the head gasket is bad.

 

^^^Already did both things you just said. Only thing thats left that i haven't done, its a leakdown test.

 

And i am loosing very little coolant.

 

How do you know your overheating? Is it possible that your cluster may be confused or misreading? Have you tried another ECU? Is the engine just insanely hot? Whats your oil level and whens the last change you did?

I realize some of those are a little redundant but unless you have zero oil or your electronics are malfunctioning there is zero reason why this is happening.

 

Exactly what i am saying. Oil change was done 400 miles ago, oil was real clean no weird color or milky. Oil level is always on the 2nd dot. Already tried 2 different clusters. While its "overheating" I can still touch the valve cover and not get burned and top is hot, but bottom one stays warm. Have not tried another ECU yet or tried a different temp sensor(on the head).

 

Also when the car is "overheting", it still drives strong and doesn't loose any power, missfire, smoke, etc...

 

Note, I am not expert and I don't gamble a lot but I would put money on a faulty sensor or thermostat.

----Now, I haven't personally tested my civic's thermostat but I remember when I had my 350 in my truck I had overheating issues and my father showed me that you can take the "thermo" off and dip it in boiling water to see if it trips. Granted this is an older engine and I have yet to do research on honda "thermos."

I am assuming that you just see the temp climbing on the cluster?!? If your civic is anything like mine you might as well just starting replacing a bunch of crap until HT comes up with an answer or it works, ha ha. If you remember please post your solution or PM me.

 

Tried 3 thermostat and did put them in boiling water, and they did open and close properly..so it isn't the thermostat. I guess i'll try replacing the sensor, but I don't understand why it would spit back antifreeze in the reservor. NO bubbling either.

 

I had that exact same problem, man. Twice.
The first time it was simply a bad radiator cap. It mimicked all the
symptoms of a blown HG.

The next time, it was overheating a little more often and had a bad
habit of filling up the reservoir and not sucking the coolant back into
the radiator after the car wasn't running. That time, it was a blown
HG. It also had the stiff / hard hoses from pressure being pushed
into the cooling system..which was also the cause of the coolant
being spit into the reservoir.

 

Thanks man. I guess thats my problem.

 

Is this solved?

 

Nope.

 

I have the same problem presently, and I cannot find the solution. It only over heat when I really drive the car hard for long. You tired changing the head gasket yet?

 

No, but everyone is leading me that direction..so i'm pulling the head today. Will update.

 

well i am doing the same tomorrow too

 

anything yet

 

well i found my problem it was the head gasket that was blown