My Car Is Overheating

[DCEVZES300]

it overheats at long stops. when is running is above the normal temperature. i just checked if it had a damage thermostat and it doesnt have a thermostat. the radiator has been flushed. do you guys think is overheating because of no thermostat? here are some pics of the missing thermostat.

[George_Jetson]

No thermostat will cause cooling problems, but chances are someone pulled the thermostat out to "fix" a overheating problem. Do you have a 92/93, with the hydrolic cooling fan? Is it working? The fan should spin slowly when the car is cold, and speed up when it gets hot. If it doesn't, find out why.

[DCEVZES300]

No thermostat will cause cooling problems, but chances are someone pulled the thermostat out to "fix" a overheating problem. Do you have a 92/93, with the hydrolic cooling fan? Is it working? The fan should spin slowly when the car is cold, and speed up when it gets hot. If it doesn't, find out why.

i am not sure wats the 92/93? is it hydrolic fluid? the fan is working though.

[George_Jetson]

What year ist your car? The 92's and 93's had a hydrolic fan, it is run by oil pressure. The fan allways spins slowly on this type of setup, but that means nothing. You have to verify that it is running at full speed once the engine starts getting hot. It will be very obvious when the fan is running at full speed. Just sit and watch it.

[CUMan]

There is a connector which plugs into the rear of the power steering pump. This connector carries a signal from the engine cooling ECM (under the glove compartment) to the power steering pump. When the cooling ECM detects the need for more cooling, a signal is sent through this connector to a solenoid in the PS pump. This causes the PS pump to circulate more fluid, thereby speeding up the cooling fan.

For some reason, this connector is often left unattached when engine work is completed. The result is that the fan does not speed up when more cooling is needed. The engine temperature will probably be okay when the car is moving at speed, since the air movement over the radiator is enough to provide sufficient cooling. However, when the car is sitting at idle or moving very slowly, it needs more fan speed to provide cooling.

Look for a wire harness hanging loose somewhere in the area of the PS pump.

[DCEVZES300]

There is a connector which plugs into the rear of the power steering pump. This connector carries a signal from the engine cooling ECM (under the glove compartment) to the power steering pump. When the cooling ECM detects the need for more cooling, a signal is sent through this connector to a solenoid in the PS pump. This causes the PS pump to circulate more fluid, thereby speeding up the cooling fan.

For some reason, this connector is often left unattached when engine work is completed. The result is that the fan does not speed up when more cooling is needed. The engine temperature will probably be okay when the car is moving at speed, since the air movement over the radiator is enough to provide sufficient cooling. However, when the car is sitting at idle or moving very slowly, it needs more fan speed to provide cooling.

Look for a wire harness hanging loose somewhere in the area of the PS pump.

ok thanks. i check that tomorrow morning. i hope its that. oooh i went into a mechanic shop and they told me that it doesnt have a thermostat because it overheated wit the previous owner. and they took it out to make the car cooler. seems that something else is wrong. im starting to think that it may be the head gasket that it started to crack or the water pump.

[DCEVZES300]

What year ist your car? The 92's and 93's had a hydrolic fan, it is run by oil pressure. The fan allways spins slowly on this type of setup, but that means nothing. You have to verify that it is running at full speed once the engine starts getting hot. It will be very obvious when the fan is running at full speed. Just sit and watch it.

my car is a 93 lexus es300, evzfe, v6.

[George_Jetson]

Other than overheating, how does it run? Are you loosing anti-freeze? Do you see white smoke from the exhaust? You did not indicate any other symptoms of a head gasket problem. Purchase a good quality thermostat, and install it. Check your power steering fluid, make sure that it is at the proper level. Start the car and monitor the cooling fan. It will always be turning, but you should notice it speed up once the engine starts getting hot. As CUMan mentioned, check the wire on the connector on the power steering pump. This solinoid is what controls the rad fan.

If the fan speed does not speed up, check to see if there is voltage going to the soliniod. At this point you wll either need to look at the sol, temp sensor, or the controller, depending on what you have found.

PS. whoever pulled the original thermostat out, without replacing, is miss-informed. You must have a thermostat, or restrictor installed. Otherwise the coolant will circulate thru the rad too fast to work properly. I would be concerned with taking my car to a mechanic that would recomend leaving the thermostat out.

[camlex]

Should be Thermostat on inlet side of Engine?

[George_Jetson]

according to my service manual, that's were the thermostat should be. Not all cars have it on the inlet, but do

[DCEVZES300]

Other than overheating, how does it run? Are you loosing anti-freeze? Do you see white smoke from the exhaust? You did not indicate any other symptoms of a head gasket problem. Purchase a good quality thermostat, and install it. Check your power steering fluid, make sure that it is at the proper level. Start the car and monitor the cooling fan. It will always be turning, but you should notice it speed up once the engine starts getting hot. As CUMan mentioned, check the wire on the connector on the power steering pump. This solinoid is what controls the rad fan.

If the fan speed does not speed up, check to see if there is voltage going to the soliniod. At this point you wll either need to look at the sol, temp sensor, or the controller, depending on what you have found.

PS. whoever pulled the original thermostat out, without replacing, is miss-informed. You must have a thermostat, or restrictor installed. Otherwise the coolant will circulate thru the rad too fast to work properly. I would be concerned with taking my car to a mechanic that would recomend leaving the thermostat out.

my car runs ok. well its the first lexus i have driven. well seems like my car has no torque. if am at a stop and i floor it the car doesnt peel out, i feel like it looses power but then it just go. i dont know if its normal but my girlfriends car can do burnouts, her car is an infinity i30. i know there are differents but her car is also a v6. i raced a 4 banger a month ago and she beated me.

[George_Jetson]

I have a 93 also. If you are looking for a car that will do burnouts, you bought the wrong car. Once these cars get moving, they can get you there fast enough to get you a ticket or two. So what I'm hearing is that other than overheating, you have no other indications of a blown head gasket. Have you done any further troubleshooting of the fan?

[DCEVZES300]

I have a 93 also. If you are looking for a car that will do burnouts, you bought the wrong car. Once these cars get moving, they can get you there fast enough to get you a ticket or two. So what I'm hearing is that other than overheating, you have no other indications of a blown head gasket. Have you done any further troubleshooting of the fan?

it seems to be working. it starts slow, then when the car is getting hotter it starts to spin faster. im not saying that i want to do burnouts. wat i was saying that i feel like this car has no torque. do you think all that things i mentioned indecates of a blown head gasket? im not sure how to check the head gasket i know i can test it with a quemical. but its around 50 bucks. i rather wait til monday and take it to a mechanic shop to have them check it for me. the owner of the shop is my friend. but i dont like to depend on friends but i dont think he would give me a bad advice.

[DCEVZES300]

Other than overheating, how does it run? Are you loosing anti-freeze? Do you see white smoke from the exhaust? You did not indicate any other symptoms of a head gasket problem. Purchase a good quality thermostat, and install it. Check your power steering fluid, make sure that it is at the proper level. Start the car and monitor the cooling fan. It will always be turning, but you should notice it speed up once the engine starts getting hot. As CUMan mentioned, check the wire on the connector on the power steering pump. This solinoid is what controls the rad fan.

If the fan speed does not speed up, check to see if there is voltage going to the soliniod. At this point you wll either need to look at the sol, temp sensor, or the controller, depending on what you have found.

PS. whoever pulled the original thermostat out, without replacing, is miss-informed. You must have a thermostat, or restrictor installed. Otherwise the coolant will circulate thru the rad too fast to work properly. I would be concerned with taking my car to a mechanic that would recomend leaving the thermostat out.

my car is not leaking. and i dont see no white smoke or any kind of smoke from the exhaust.

[DCEVZES300]

There is a connector which plugs into the rear of the power steering pump. This connector carries a signal from the engine cooling ECM (under the glove compartment) to the power steering pump. When the cooling ECM detects the need for more cooling, a signal is sent through this connector to a solenoid in the PS pump. This causes the PS pump to circulate more fluid, thereby speeding up the cooling fan.

For some reason, this connector is often left unattached when engine work is completed. The result is that the fan does not speed up when more cooling is needed. The engine temperature will probably be okay when the car is moving at speed, since the air movement over the radiator is enough to provide sufficient cooling. However, when the car is sitting at idle or moving very slowly, it needs more fan speed to provide cooling.

Look for a wire harness hanging loose somewhere in the area of the PS pump.

i found a connector that isnt plug. i dont see where to plug it. its right behind the passenger headlight. all connectors are plug into the headlight but that one is. ima go and take a picture of it. to show you what im talking about.

[DCEVZES300]

here are some pictures of the connector that i found unplug. i dont know if its has something to do with my overheating problem. i dont think is it but i am hoping in all other ways before assuming is the head gasket.

[George_Jetson]

Look for the solenoid on the power steering pump, there should be a wire going to it. If not, you have found the problem.

[DCEVZES300]

Look for the solenoid on the power steering pump, there should be a wire going to it. If not, you have found the problem.

can you plz tell me where is the solenoid?

[George_Jetson]

Here's a picture, I don't think you have a issue with the headgasket. I"ll bet there is something with your fan control.

[DCEVZES300]

Here's a picture, I don't think you have a issue with the headgasket. I"ll bet there is something with your fan control.

i also think that. look i turn my car on. and wait til it gets hot and i go and put my hand close to the fan and i feel no fresh air. no air at all.

[George_Jetson]

Hook a voltmeter up the the wire on the solenoid. Route the wire so that it will be clear of the belts. Run the car and see if you are getting power to it once it gets hot.

[DCEVZES300]

Hook a voltmeter up the the wire on the solenoid. Route the wire so that it will be clear of the belts. Run the car and see if you are getting power to it once it gets hot.

oooh man you are my life saver. i just went underneath the car and i checked the power steering pump and i saw it was unplug. so now i got to hook it. wow i owe you man. you were the only one helping me out. i still gotta plug it and see wat happens

[George_Jetson]

Sounds like you've got it, verify that it is working properly, and I would strongly suggest installing a good thermostat of the correct heat range. The ECM really wants to see the engine reach operating temp. I am glad we could help, there a quite a few people here that are more than glad to try to help. good to hear when things do go well.

[DCEVZES300]

Sounds like you've got it, verify that it is working properly, and I would strongly suggest installing a good thermostat of the correct heat range. The ECM really wants to see the engine reach operating temp. I am glad we could help, there a quite a few people here that are more than glad to try to help. good to hear when things do go well.

when i plug it. i turned my car on and i watched the fan til it got warm. i felt fresh air coming out of the fan. the gauge is right underneath the top line. is that normal? or it has to be above the lower line? ima go and check the plugs to see if they are working perfectly. on the ECM, is there any switch or something to have the car cooler? like something to make more pressure for the fan?

[George_Jetson]

fancontrol.bmp

Here is a attachment that shows the fan controller, major overengineered on toyota's part