My car wont reach the normal operating temperature.
03-30-08, 02:27 PM
#17
Did you use a factory water pump, factory thermostat and factory thermostat gasket? The factory stat has a built in air bleeder valve so the cooling system will purge itself of air bubbles.
Normally there are only two causes of overcooling:
1) A stuck open thermostat or a kinked thermostat gasket that allows coolant to flow full time past the thermostat.
2) A fan clutch that's frozen in the engaged position.
It's very important to meansure the amount of coolant drained so you'll know how much needs to go back into the system.
Normally there are only two causes of overcooling:
1) A stuck open thermostat or a kinked thermostat gasket that allows coolant to flow full time past the thermostat.
2) A fan clutch that's frozen in the engaged position.
It's very important to meansure the amount of coolant drained so you'll know how much needs to go back into the system.
03-30-08, 03:52 PM
#20
I agree with PD on the gauge.. which is why I indicated not to rely on it. Was the temp gauge , apparently, reading a bit under halfway before you made this change?
Like I said, I would do what I mentioned, and get some sort of meter to measure the actual temperature. You can use a cooking utility if you have it -- Just something that will go to 200F or so.
Like I said, I would do what I mentioned, and get some sort of meter to measure the actual temperature. You can use a cooking utility if you have it -- Just something that will go to 200F or so.
03-30-08, 04:29 PM
#21
Ok, here's the deal. When I changed the water pump, I also did a flush - well, I drained all old coolant, filled it with distilled water, ran it through the system, drained it and filled with 50/50 Toyota red antifreeze and distilled water.
All my parts are OEM, including water pump and thermostat.
Here's what I seems to be happening. I ran the car today for a good hour with radiator cap open and heat blasting on full., and the temperature just stays a tiny bit above the first line. The coolant inside the reservoid is cold to the touch. The hose that runs from the radiator to the engine (on the drivers side) didnt have any fluid in, I squeezed it a few times, and air bubbles were coming out from the open reserviod, and the hose would suck in some fluid. Also, until I started squeezing that hose, it was barely warm, but once it filled with fluid it became pretty hot.
Here's what I think is happening. I think my thermostat isnt opening, or not opening enough, and there's no flow through the radiator. I bet my radiator is full of air right now, or just standing fluid. But its beyond me whats keeping the fluid not to get hot enough to open up the thermostat. I know the pump is working properly because when I open up the inlet housing, I can see the fluid streaming through the ICV hose thats connected to the inlet housing.
I'm going to try what PD suggested by jacking the car up. Can I just drive it onto a steep hill? By the way, the first gen LS does not have a radiator cap per say, its actually a reservoir cap.
All my parts are OEM, including water pump and thermostat.
Here's what I seems to be happening. I ran the car today for a good hour with radiator cap open and heat blasting on full., and the temperature just stays a tiny bit above the first line. The coolant inside the reservoid is cold to the touch. The hose that runs from the radiator to the engine (on the drivers side) didnt have any fluid in, I squeezed it a few times, and air bubbles were coming out from the open reserviod, and the hose would suck in some fluid. Also, until I started squeezing that hose, it was barely warm, but once it filled with fluid it became pretty hot.
Here's what I think is happening. I think my thermostat isnt opening, or not opening enough, and there's no flow through the radiator. I bet my radiator is full of air right now, or just standing fluid. But its beyond me whats keeping the fluid not to get hot enough to open up the thermostat. I know the pump is working properly because when I open up the inlet housing, I can see the fluid streaming through the ICV hose thats connected to the inlet housing.
I'm going to try what PD suggested by jacking the car up. Can I just drive it onto a steep hill? By the way, the first gen LS does not have a radiator cap per say, its actually a reservoir cap.
03-30-08, 07:18 PM
#24
The coolant is most definitely not getting to certain areas of the engine. If it is cold to the touch then it is not circulating through the engine, which is , obviously, very dangerous.
It could be the thermostat not opening, but if you replaced it I wouldn't see why. Maybe put your old one back on. Also make sure it is facing the right direction I suppose. (It might not be able to go but in one direction I am not sure).
can you remove the thermostat and close it back up (without a t-stat in place) so that it is constantly open? That could test that theory when running the vehicle.
Definitely need to get that fluid circulating one way or another, and there are only so many possibilities of why it isn't circulating.
A) Big air in the system
B) Blockage of some kind.
C) T-stat not opening
D) ZERO pressure, fluid unable to move.
E) Waterpump faulty, and not moving the coolant.. coolant is basically standing still. (Have you verified the Waterpump is functioning?)
That is about it.
The car , IIRC, measures temperature to the temp reading on the instrument cluster via a sensor in the coolant. So it doesn't necessarily reflect the true temperature of the engine, but that of the coolant.
However, I am thinking I am very wrong on this one
-- I think what I am thinking of is simply a sensor to dictate whether the coolant is low or not, and thus sends a 'cluster light' low coolant warning.
Anyone verify this? Does the actual temp sensor reside in the engine area, or just on the return line or something of the 'hottest' area of the coolant?
PD makes a good point as well -- The radiator/overflow and general system of the LS 400 is a bit different than other vehicles. I know, at least, on the Gen I's there is no Radiator cap right there in front like most vehicles -- But the reservoir to the right hand side. I am not even sure where you fill , and where the cap is on my car =)
I topped it off once via the reservoir, but if I was doing a drain/flush I would figure out where the proper intake was.
You might have fluid in a certain area and none in other vital areas. Still, it should circulate one way or another. However, if there is no fluid and (pressure) in and around the water pump then it won't move the coolant you have in the area you filled it in. (You could gauge by the capacity readings from manual, and how much you put in as well). IE: If it reads 5 quarts for a full capacity, and you only are able to get in 3, then you know something is off, (unless it is old residual coolant, but I'd drain it fully if possible).
The numbers are just for example,.. of course not accurate.
I'd be very careful with this and not drive the car until you get it sorted. (Which I think you are already doing -- That is I believe you are already taking the proper precautions)
Also, don't pull your hair out, you will get this worked out.. =)
It could be the thermostat not opening, but if you replaced it I wouldn't see why. Maybe put your old one back on. Also make sure it is facing the right direction I suppose. (It might not be able to go but in one direction I am not sure).
can you remove the thermostat and close it back up (without a t-stat in place) so that it is constantly open? That could test that theory when running the vehicle.
Definitely need to get that fluid circulating one way or another, and there are only so many possibilities of why it isn't circulating.
A) Big air in the system
B) Blockage of some kind.
C) T-stat not opening
D) ZERO pressure, fluid unable to move.
E) Waterpump faulty, and not moving the coolant.. coolant is basically standing still. (Have you verified the Waterpump is functioning?)
That is about it.
The car , IIRC, measures temperature to the temp reading on the instrument cluster via a sensor in the coolant. So it doesn't necessarily reflect the true temperature of the engine, but that of the coolant.
However, I am thinking I am very wrong on this one
-- I think what I am thinking of is simply a sensor to dictate whether the coolant is low or not, and thus sends a 'cluster light' low coolant warning.Anyone verify this? Does the actual temp sensor reside in the engine area, or just on the return line or something of the 'hottest' area of the coolant?
PD makes a good point as well -- The radiator/overflow and general system of the LS 400 is a bit different than other vehicles. I know, at least, on the Gen I's there is no Radiator cap right there in front like most vehicles -- But the reservoir to the right hand side. I am not even sure where you fill , and where the cap is on my car =)
I topped it off once via the reservoir, but if I was doing a drain/flush I would figure out where the proper intake was.
You might have fluid in a certain area and none in other vital areas. Still, it should circulate one way or another. However, if there is no fluid and (pressure) in and around the water pump then it won't move the coolant you have in the area you filled it in. (You could gauge by the capacity readings from manual, and how much you put in as well). IE: If it reads 5 quarts for a full capacity, and you only are able to get in 3, then you know something is off, (unless it is old residual coolant, but I'd drain it fully if possible).
The numbers are just for example,.. of course not accurate.
I'd be very careful with this and not drive the car until you get it sorted. (Which I think you are already doing -- That is I believe you are already taking the proper precautions)
Also, don't pull your hair out, you will get this worked out.. =)
Last edited by Neofate; 03-30-08 at 07:22 PM.
03-30-08, 08:16 PM
#25
Definitely need to get that fluid circulating one way or another, and there are only so many possibilities of why it isn't circulating.
A) Big air in the system
B) Blockage of some kind.
C) T-stat not opening
D) ZERO pressure, fluid unable to move.
E) Waterpump faulty, and not moving the coolant.. coolant is basically standing still. (Have you verified the Waterpump is functioning?)
A) Big air in the system
B) Blockage of some kind.
C) T-stat not opening
D) ZERO pressure, fluid unable to move.
E) Waterpump faulty, and not moving the coolant.. coolant is basically standing still. (Have you verified the Waterpump is functioning?)
That is about it.
The car , IIRC, measures temperature to the temp reading on the instrument cluster via a sensor in the coolant. So it doesn't necessarily reflect the true temperature of the engine, but that of the coolant.
However, I am thinking I am very wrong on this one -- I think what I am thinking of is simply a sensor to dictate whether the coolant is low or not, and thus sends a 'cluster light' low coolant warning.
The car , IIRC, measures temperature to the temp reading on the instrument cluster via a sensor in the coolant. So it doesn't necessarily reflect the true temperature of the engine, but that of the coolant.
However, I am thinking I am very wrong on this one
-- I think what I am thinking of is simply a sensor to dictate whether the coolant is low or not, and thus sends a 'cluster light' low coolant warning.1) The main ECT sensors - sends coolant temperature info to the ECU, for a/f ratio.
2) Cooalnt temperature sender - the sensor that sends temperature info to the cluser gauge.
3) Cold start temperature sensor - actually a swith for cold start injector.
4) Radiator coolant temperature sensors - responsible for turning radiator fans on and off when coolant reaches certain temperature.
5) Coolant level sensor - thats in the reservoid, and when the coolant level is low, it triggers the warning light on the cluster.
Speaking of #4, my radiator fans never turn on either, which is another indication that my coolant never reaches normal temperature.
PD makes a good point as well -- The radiator/overflow and general system of the LS 400 is a bit different than other vehicles. I know, at least, on the Gen I's there is no Radiator cap right there in front like most vehicles -- But the reservoir to the right hand side. I am not even sure where you fill , and where the cap is on my car =)
I topped it off once via the reservoir, but if I was doing a drain/flush I would figure out where the proper intake was.
I topped it off once via the reservoir, but if I was doing a drain/flush I would figure out where the proper intake was.
You might have fluid in a certain area and none in other vital areas. Still, it should circulate one way or another. However, if there is no fluid and (pressure) in and around the water pump then it won't move the coolant you have in the area you filled it in. (You could gauge by the capacity readings from manual, and how much you put in as well). IE: If it reads 5 quarts for a full capacity, and you only are able to get in 3, then you know something is off, (unless it is old residual coolant, but I'd drain it fully if possible).
The numbers are just for example,.. of course not accurate.
I'd be very careful with this and not drive the car until you get it sorted. (Which I think you are already doing -- That is I believe you are already taking the proper precautions)
Also, don't pull your hair out, you will get this worked out.. =)
The numbers are just for example,.. of course not accurate.
I'd be very careful with this and not drive the car until you get it sorted. (Which I think you are already doing -- That is I believe you are already taking the proper precautions)
Also, don't pull your hair out, you will get this worked out.. =)
03-30-08, 10:51 PM
#26
Lexus Test Driver
Aside from the obvious need for hot coolant to heat the heater core, the engine is most efficient at operating temperature. If the engine is never reaching operating temperature, there will be losses in efficiency and possibly additional wear on engine parts. There is a direct relation between coolant temperature and engine temperature.
03-31-08, 12:01 AM
#27
It seems that its circulating through the engine, - when I open up the inlet housing bolt I see the coolant flowing. But It doesn't seem to flow through the radiator, or at least not properly flowing through the radiator. However now that I'm thinking about it, the radiator was very hot.
If the radiator is getting hot , then good.
--Can you take a pressure reading of your system. This would indicate any blockage or leaks.
It's actually the 2nd thermostat that I just installed. I though the car wasnt reaching the normal temperature because the previous thermostat was opening prematurely, welp, same thing with the new one. I tested the old one today by placing it into a bowl with water and heating the water up. It opened up like prescribed, before the water started to boil. I guess it was working properly - its suposed to open at 82C.
I was thinking about that, but what happens once I install the thermostat?
*I only mean do this in your driveway, maybe for a short drive.. not leave it out for the day while you go to work and such.
Well, waterpump is functioning for sure. With the old waterpump which was leaking my car was overheating. This new pump is defenately pushing the fluid as it suposed to, but apparently theres a blockage somewhere.
As far as I know there are many different coolant sensors.
1) The main ECT sensors - sends coolant temperature info to the ECU, for a/f ratio.
2) Cooalnt temperature sender - the sensor that sends temperature info to the cluser gauge.
3) Cold start temperature sensor - actually a swith for cold start injector.
4) Radiator coolant temperature sensors - responsible for turning radiator fans on and off when coolant reaches certain temperature.
5) Coolant level sensor - thats in the reservoid, and when the coolant level is low, it triggers the warning light on the cluster.
Speaking of #4, my radiator fans never turn on either, which is another indication that my coolant never reaches normal temperature.
The first 3 are inside a metal housing that's just before the thermostat housing, on the engine side, so coolant flows through them constantly, and therefore they should be pretty accurate in relation of engine temp to the coolant temp.
Well, I've been driving the car like this for a while now, with seemingly no problem, but I'm getting concerned as the weather is getting warmer. Thing is, I am sure the car is running colder than normal, during some winter moth I was able to drive the car for several hours, and then open the hood and put my hand on the intake manifold, and it would be barely warm to the touch. I'm sure that's not very normal. If I dont figure the problem out myself, I'm defenately gonna have the mechanics take a look at it the next time I change oil.
Well, having it run 'under' normal operating temperature isn't going to cause major damage.. it is the reverse that does. That said, not running up to close to operating temp. isn't good for it in the long haul -- You need to get this sorted out and relatively soon.
I don't know about having a jiffy lube check my coolant system. Though I don't know where you get your oil changed. If its a good indie mechanic, then that sounds like a plan. They should get you straightened out.. Just let them know all you have done, and the symptoms of course.
When you figure it out, or have it figured out -- Do let us know the issue.
Good luck!
03-31-08, 01:59 AM
#28
That bolt on top of the thermo housing is for bleeding the air out of the system, not filling it.
I would take out that bolt drain it again, then fill from the rad cap, having that bolt out allows the fluid to fill from the bottom up SMOOTHLY, and reduces the chance of a big air bubble forming.
By filling it from the point you did, you may have caused an air bubble,,, its like when you dump out a 2 liter bottle and it makes that chug chug chug sound... liquid going out, air going in thru the same hole, same thing only the liquid is going down in the engine and air out... But they interfere with each other, you dont want that.
Make sure the T stat is in the right way, also you could drill a small hole thru the flat part... this can allow some fluid to move all the time, might bleed the air off more easily.
One last thing, if you overheated the car previously with a leaking water pump, you may have caused a head gasket failure, when that happens often combustion gas, is pushed into the coolant system making large air bubbles that wont go away. (but they also usually pressurize the coolant system and you said there was no pressure) You can have the coolant tested for exhaust gas.
Hope that helps. and good luck with it
Ken
I would take out that bolt drain it again, then fill from the rad cap, having that bolt out allows the fluid to fill from the bottom up SMOOTHLY, and reduces the chance of a big air bubble forming.
By filling it from the point you did, you may have caused an air bubble,,, its like when you dump out a 2 liter bottle and it makes that chug chug chug sound... liquid going out, air going in thru the same hole, same thing only the liquid is going down in the engine and air out... But they interfere with each other, you dont want that.
Make sure the T stat is in the right way, also you could drill a small hole thru the flat part... this can allow some fluid to move all the time, might bleed the air off more easily.
One last thing, if you overheated the car previously with a leaking water pump, you may have caused a head gasket failure, when that happens often combustion gas, is pushed into the coolant system making large air bubbles that wont go away. (but they also usually pressurize the coolant system and you said there was no pressure) You can have the coolant tested for exhaust gas.
Hope that helps. and good luck with it
Ken
03-31-08, 07:40 AM
#29
Ok an update.
This morning when the car was cold, I opened the radiator cap and squeezed the air out of the radiator house, while adding coolant. Once the hose felt "full", I closed the radiator cap, and drove the car for a couple of miles. After that I tried sqeezing the radiator hose, and it was nice and tight, very hard to sqeeze at all. So I opened the radiator cap, and the coolant squirted out of there. Good thing I was wearing a glove, otherwise I would be burned.
So now, that means that the pressure is building up just fine, and there's no more air in the system. Great, but the car still doesn't reach its normal temperature. The thing is, I would think that its the temperature sender unit, but that cant be, because the radiator fans never turn on either, and they are controlled by a different sensor/switch. Even with the AC button on, the fans do not come on. I don't know what else to think.
This morning when the car was cold, I opened the radiator cap and squeezed the air out of the radiator house, while adding coolant. Once the hose felt "full", I closed the radiator cap, and drove the car for a couple of miles. After that I tried sqeezing the radiator hose, and it was nice and tight, very hard to sqeeze at all. So I opened the radiator cap, and the coolant squirted out of there. Good thing I was wearing a glove, otherwise I would be burned.
So now, that means that the pressure is building up just fine, and there's no more air in the system. Great, but the car still doesn't reach its normal temperature. The thing is, I would think that its the temperature sender unit, but that cant be, because the radiator fans never turn on either, and they are controlled by a different sensor/switch. Even with the AC button on, the fans do not come on. I don't know what else to think.
03-31-08, 10:41 AM
#30
but seriously, you probably just have a bad thermostat.