How do you "Burp" the cooling system (3S GE)?

There's a couple ways to do it.

On a cold motor:
Start the car.
Take off the radiator cap
Let the engine come up to temp.
Keep topping off the fluid when it gets low (you'll start to see the fluid moving through the radiator with occasional air bubbles).


The other way is to hang the resovior from the hood, fill it up & let the car run with the cap on. The air'll get forced out.

 

Best way is start the car cold, uncap the radiator, blast the heater at full, and let it spill over as the bubbles come out. Fill as needed.

 

with the motor turned off i fill it up, close rad cap, then run the motor for like 20 seconds to get it circulating, then open the rad cap, pulse squeeze both hoses, you'll see bubbles coming out with every squeeze until it's full.

 

for whatever reason i couldnt get 09 fully burped one time... so i pulled one of the hoses from the iac valve on the bottom of the throttle body. run the car till coolant comes out, then stuff the hose back on.

 

I have never had to burp the system it allways just works itself out just as long as you have
fluid in the overflow container, at worst you would have to cycle the heater control from cold
to hot to circulate coolant through the heating system.

Anyways you have replaced the temp sensor on the intake pipe close to the altenator.
This sensor is used to control your fan only.........




I am guessing that your temp guage is still jumping around after your repairs

You need to test the sensor for the temp guage not the fan sensor, this is the sensor
that will send a signal to the ECU.




The temp guage sensor is the top left sensor on the water outlet neck, in this picture I have
replaced the original connector with a crimp on connector, it's just below the oil pressure sensor
Start by making sure you have a good connection between the sensor and the plug, as I allready
noted I replaced my original plug because it had a flakey connection


If you still think your fans are a problem let me know and I'll show you how to wire them to be turned on
automatically when the engine starts.

 

There is a relay for the fan heres how to test it


The relay is in the main fuse box in the engine bay


It also suggests testing the Engine Main Relay which is also in the main fuse box in the engine bay


If all that doesn't work I would suggest taking out the thermostat all together so
you are guaranteed a constant flow of coolant. This would just be temporary to see
if it solves your overheating issue. It does mean it will take the car a bit longer to
warm up but your running out of other options.

It's a mechanical water pump run of the timing belt so it has to work, the only thing
that ever fails on it is the bearing so you have to be pumping coolant.

 

You have said before that the problem is intermitent and this normally points to an electrical issue
Mecanical systems either work or don't but electrical systems sometimes become intermitent. Just
look at our 4th gen starter issue. I think we can assume that your engine is indeed overheating, 2
different temp senders have produced the same results on your temp guage so we need to figure
out why the cooling system isn't working properly.

Thermostat - you have tested/ tried 2 of them and its not an electrical system so it's unlikely to
become intermitent

Radiator - your radiator may become clogged with crap and reduce the amount of coolant that can
flow through it but once again it's a mechanical system so overheating wouldn't be intermitent it
would be constant.

Fan - the fan motor has brushes that wear out with time, never seen it happen but it is theoretically
possible

Fan Relay - relays are know to become intermitent, once again I remind you of our starter problem, I
bet 7 out of 10 times I try to start my car I have to bypass the starter relay.............

Radiator Hose - perhaps your inlet radiator hose the one attached to the thermostat is so old and
soft that it is colapsing when coolant is sucked through it reducing the amount of coolant that can
flow through the engine. Once again a mechanical system so not prone to intermitent falures

I would recommend by-passing the fan relay and run your fan constantly as a test to see if that
solves your overheating issues. I really don't trust 24 year old relays and have run the cooling
fans on my Celica constantly for the last 2 years. Your probably going to burn out the fan motor a
bit sooner and your going to waste a bit of electricity but your not going to do any harm to the
engine.

How long have you owned the car?
Has it allways had this problem?
Have you ever used a "STOP LEAK" product in the cooling system?
What does the coolant look like?

 

theirs only 2 real scenarios

- either the coolant isn't flowing fast enough
- it's not getting cooled enough when flowing through the radiator

So you have to determine if its a flow rate issue or an inability for the heated coolant
to cool back down.

Do you have an infra red temp guage ? Their pretty cheap to get, if you can measure
the temp of the 2 radiator hoses once the engine is warm, hopefully the one attahed
to the thermostat is quite a bit cooler than the coolant return hose.

 

Before you do anything else, do a compression test. How do your spark plugs look?

My old white '89 did the same thing. I had to do an upper rebuild (head gasket)