16 4age wont warm up

[Rice86]

car- ae86
engine - JDM RWD 16 4age

Issue - Car stopped warming up for the past 2 days
Car used to heat up to 85deg-90deg as shown on water temp gauge, not anymore
car does not pass 30deg in the morning, driving home after work *peak heat of the day* only brought temp up to 40deg-60deg

troubleshoot - Have replaced thermostat with brand new one
- Have flushed all coolant and bled water system to best of my knowledge and know how
- no water leaks anywhere
- radiator is not blocked or leaking or damaged

Comments - could it be the water pump?
-pulled off the top outlet hose from top water outlet that goes to top of jdm radiator.. water seems to be flowing out while car is on
but flow seems slow? water still wont get hot for thermostat to open
-when all hose are connected, there is now water flowing when looking into the radiator cap opening
- other then the idea of the water pump failing, i now am lost of what next to do
- the head of the engine still gets hot, not sure if hotter then usual
-could it be a sensor or something?

Pulling out of skidpan tomorrow as this needs to get sorted out before i blow a head-gasket or something worse

[Vaughn]

If everything seems to be fine
Could it be your gauge or sensor failing?
Make sure its all plugged and clean and what not
If you touch the top hose into the radiator is it hot(after driving around)?

[Rice86]

top hose is hot
bottom hose that leads to thermostat is basically cold, i can hold onto the hose forever even while the engine is turned on....and this is after 1hour worth of driving

[Matt]

Did you replace gas thermostat rubber when you installed the thermostat?

[sundee]

This all makes no sence - if all of the things you mentioned were failing the temperature would be thru the roof! engine bay temps would be massive!

its either your gauge but most likley your temp sensor, cheap and easy to replace.

[Vaughn]

I would be doing this first

But as i said take the sensor out and give it a clean

If you can clearly feel that the top hose is hotter then what the gauge says there is obviously something electrical that is sensing incorrect measures

[Rice86]

Ok guys I've checked everything, water pump is like still brand new when I pulled it off yesterday so that's fine
Temp gauge is fucked, boiled hot water and threw the temp sensor in, nothing so reading

But all that still does not explain the lost in power from 2000 to 7500, and the thermostat not opening

I have tested and took out the thermostat, I have now got all my power back and drives like normal now BUT the engine is always thinking it's on cold start up without thr thermo, engine stays at 1500 rev. Would disabling the cold start make the engine idal at 1000 again hot or cold?

I really don't know why my brand new thermostat won't open, but again the coolant still wouldn't get hot enough before anyways


This is Sooooooo weird, never had a 4age stay this cold before... Only over heat

[sundee]

Boil some water on a stove, throw the thermostat on with a thermometer and check the opening temperature. Or if it's opening at all.
You were loosing power thru the water pump I'd say. With the thermostat not opening its blocking the flow of water out of the engine causing massive resistance.

Replace the sensor!
Check that thermostat . I once got an 82' thermostat that didn't open untill 96'!
Don't buy a cheap one!

[Rice86]

i will boil water on a stove and throw both the old and new thermostat in after work, and see WTF is going on..

the engine still ideals at 1500rpm with thermostat not installed and im thinking its cold start related as it still does not get hot to operating temperature.

so how does one DISABLE cold start? just want to know in case i do have to take that option

[Rice86]

so i boiled water in a stove and threw both the old and new thermostat in, and both did open, so both are working

i couldn't record at what temp this opened at because i have no tool for his but i know both of them still work

i decided to install the brand new one back into the car and again after installation, lost power again in the engine due to thermostat wont open, took it for a test drive and tried to make the water hot, would not open still

the radiator top half gets hot and bottom half stays cool/colder then the top with thermostat installed..its not circulating or something?

this is starting to really piss me off