The other day it was around 90-93 degrees out and my car started to overheat when it idled. I let it cool down and then I started to drive home carefully keeping a watchful eye on the temperature. I noticed the car didn't over heat when I drove, only when I idled. I went out to test the car today (it was much cooler, around 75 degrees) and it still started to overheat when it was idling.

I checked the over flow bottle and there was just a tiny amount in it, I also took the radiator cap off and there was no visible fluid.

Any Ideas??

P.S. How would I check the level of the fluid? Also, how would test the mixture to find out its current ractio??


Modified by DanielleX51 at 10:55 PM 8/2/2006

 

add fluid until visible.. nd check if u have leaks 50/50 water/coolant


Modified by sohc90rex at 7:46 PM 8/2/2006

 

This may seem like a dumb question, but you didn't mention anything about your radiator fan. Is it working?
If so, have you had reason to mess with your wiring at all? I ask because after my first motor swap, I managed to reverse my wiring going to my fan and it spun backwards, shoving hot air off the engine into my radiator instead of pulling air through it from the front of the car.

 

You've got to be losing coolant somewhere. Keep the radiator full & the reservoir somewhere between the 2 lines and see how she holds up

 

well. there are quite a few things. I just say drain your whole system and get new coolend and make sure its 50/50. Then if it still over heats then let your car cool down, or not, and let your car idle and look under your hood at your fan. If it doesnt turn on then you need a new fan switch or you can rig up your own to be able to switch it on whenever you wanted. Or else the problem could be your thermostat. But before you change that you will want to burp your system. Which means turn your car on and keep the radiator cap off and let it idle. You might see some bubbles come up when the coolent it cycled through the engine. And if it still over heats then its your thermostat. And when you instal that you need to make sure the little ball is in the up position.

 

It's not the thermostat, it would overheat while moving too, sounds like the fans not kicking on, or your possibly low on coolant, or a combination! Since you said there was fluid in the overflow at all it sounds like its the fan for sure.

 

dont forget that there might be a air pocket on the thermostat. So burping it might take care of it for sure

 

It's been real hot here in LA lately so without the fan, I would overheat easily. I refilled about 20/80 coolant/water, bled the system, replaced the fan and all is well. I've had a bad fan for a while now, in retrospect I should have taken care of it immediately instead of risking my engine.

Make sure you have enough water/coolant, good pressure (check cap), no leaks and make sure the fan works and you should be fine.

 

I recently notice I had a similar problem. I was on my break from work and decided to turn on the car; I let it idle for about 30 minutes and suddenly the needle went above the mid line.

Not too sure if it was the fan or not but I been cautious about it ever since. When I drive its peachy and haven't had a problem of it overheating ever since.

Might do the above suggestions today.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Spoon Sports &raquo;</TD></TR><TR><TD CLASS="quote">I recently notice I had a similar problem. I was on my break from work and decided to turn on the car; I let it idle for about 30 minutes and suddenly the needle went above the mid line.

Not too sure if it was the fan or not but I been cautious about it ever since. When I drive its peachy and haven't had a problem of it overheating ever since.

Might do the above suggestions today.</TD></TR></TABLE>

You almost def. are having a radiator fan problem. Or a bubble on your thermostat. If you over heat at idle then you really need to let your car idle and pop your hood and see if your fan turns on.

 

[QUOTE=jakscivic]

You almost def. are having a radiator fan problem.QUOTE]
check your fuse and relay and fan.

 

Today I burped the radiator (I let the car idle to normal operating temperature with the radiator cap off), it seemed to slow the temperature from rising. However I think if I had given it more time it would have overheated.

Now I emailed the original owner and he said he had the same thing happen to him 3 months ago. He said that it was a bad temperature sensor, Do you think he means the thermostat? or is there actually a temperature sensor? If so where is it located?

Tomorrow I am going to buy some radiator fluid and try adding it and see how that works, while I wait for my new radiator to arrive.

 

It could also be your water pump.

 

the sensor could have been the temp sensor for your fan. You should have tried to fix the problem a bit more rather than buying a radiator. Some people try and buy their way out of the problem and its usually something easy and cheap. The new radiator might fix your problem, but then again you might have just waisted your money.

 

check your thermostat, radiator fan, and do a tamp test.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jakscivic &raquo;</TD></TR><TR><TD CLASS="quote">the sensor could have been the temp sensor for your fan</TD></TR></TABLE>

Would the fan temperature sensor be the "Fan switch" that screws in under the VTEC Solenoid?

 

Red = ECU Temp sensor
Green = Cluster Guage sender
Blue = Fan switch

[img]http://www.we-todd-did-racing.com/wetoddimage.wtdr/wMTI4NTA1NjZzNDEzZGZkMzF5NTQx.jpg/img]

 

I have a B16A2 motor swap in my rex, isn't there only 1 Fan Switch (Thermoswitch) and a Temperature Gauage Sending Unit on that engine?

Also if I remove the Thermosensor (Fan Switch) is any fluid going to come out of that hole? Because mine seems to have like an "oily" look to the inside of the switch itself, it leaves a black stain on my fingers so I am assuming it's oil.


Modified by g2tegsown at 2:48 PM 8/4/2006

 

At idle the rpm of the waterpump is slow = less water moving.
At speed, water moves faster thus cooling better.

Double check the water level. Also check the fan temp switch, it is easy to knock off. Have you messed with anything around the distributor lately?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DanielleX51 &raquo;</TD></TR><TR><TD CLASS="quote">Today I burped the radiator (I let the car idle to normal operating temperature with the radiator cap off), it seemed to slow the temperature from rising. However I think if I had given it more time it would have overheated.

Now I emailed the original owner and he said he had the same thing happen to him 3 months ago. He said that it was a bad temperature sensor, Do you think he means the thermostat? or is there actually a temperature sensor? If so where is it located?

Tomorrow I am going to buy some radiator fluid and try adding it and see how that works, while I wait for my new radiator to arrive.</TD></TR></TABLE>

i had the same problem you are experencing. and it was my temp sensor whitch is located on the pass sind of the head it is the single wire plug under thedizzy to the right.

 

i just fixed this porblem on my gsr swap. car overheated after about 15mins of idling. ......i forgot to connect the fan harness. the cooling fan's job is to cool your car while sitting motionless. radiator is only effective when air is being pushed over it. (like while driving) so when you sit at idle with no fan to move air over it you overheat

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by g2tegsown &raquo;</TD></TR><TR><TD CLASS="quote">Would the fan temperature sensor be the "Fan switch" that screws in under the VTEC Solenoid?</TD></TR></TABLE>

The Fan Temp switch is on the back of the block on OBD-0 blocks. It has two single-plug connectors. It's the Blue one in this picture:



<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b16crexster &raquo;</TD></TR><TR><TD CLASS="quote">i had the same problem you are experencing. and it was my temp sensor whitch is located on the pass sind of the head it is the single wire plug under thedizzy to the right.</TD></TR></TABLE>
The single wire plug is the sender for the water temp gauge in the dash. If this is unplugged, the gauge will fall to the lowest setting, and if there is a bad ground, the gauge will spike. This doesnt have anything to do with the car actually overheating. It just shows faulty gauge readings when there is a problem with this circuit.

To the original poster. If your car is only overheating at idle, chances are that your fan is not turning on. Have you let the car run to see if the fans will kick on?

 

well, he actually said that he has a manual fan switch in his car. So unless he doesnt turn it on when he is sitting, or the switch doesnt work.

you could always try and drain your fluid then burb it. That might do the trick. But there still has been other ideas stated that you still need to try.

 

check your water pump. My EE9 had a similar problem, and it was a almost dead water pump

 

If your temperature sending unit was bad would it still send a signal? Or would it send no signal at all? Could it send an incorrect signal? If so how would you know if it was sending an incorrect signal?

Also if I am going to add coolant to my radiator I should put it in the reservoir bottle right?