Help!!!
08-25-08, 07:43 AM
#1
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Help!!!
Just bought a 1993 Lexus es300. It runs pretty good. My only complaint is that the a/c works, but makes the car run hot!!! It's the middle of the summer in North Georgia, and I am burning up!!!
Just for good measure, my husband replaced bot the compressor and the dryer--but no luck. The fan will only blow at one speed, causing the engine to overheat. We've been told to replace the hydraulic motor control. Could this be the problem? I've read that these cars should NEVER be allowed to run hot!
AND
The transmission kicks a little too hard for my tastes when going into first gear. Is this common, or the sign of a problem? We plan our first of three fill and drains this weekend.
Just for good measure, my husband replaced bot the compressor and the dryer--but no luck. The fan will only blow at one speed, causing the engine to overheat. We've been told to replace the hydraulic motor control. Could this be the problem? I've read that these cars should NEVER be allowed to run hot!AND
The transmission kicks a little too hard for my tastes when going into first gear. Is this common, or the sign of a problem? We plan our first of three fill and drains this weekend.
08-26-08, 08:42 AM
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What you're saying I kind of get but am a bit confused. But just to try to make sense of things,
1. Have your a/c checked by a mechanic that knows about a/c systems and how they work. A/C systems are a high pressure system, and a leak within any of the hoses, fittings, etc, are enough for you to lose all the freon in the system and have nothing to cool the air within the engine (hence maybe the hot air blowing in.)
2. If the engine is running hot, that would be a "engine cooling" problem. Check your radiator for fluid levels and/or if it needs to be replaced. If you are using Toyota brand radiator fluids, it should a wonderful bright red color. If you are using generic radiator fluids, it should a bright neon green color. Any variation of browns mean that you need to change your radiator fluid and/or need an engine coolant flush
1. Have your a/c checked by a mechanic that knows about a/c systems and how they work. A/C systems are a high pressure system, and a leak within any of the hoses, fittings, etc, are enough for you to lose all the freon in the system and have nothing to cool the air within the engine (hence maybe the hot air blowing in.)
2. If the engine is running hot, that would be a "engine cooling" problem. Check your radiator for fluid levels and/or if it needs to be replaced. If you are using Toyota brand radiator fluids, it should a wonderful bright red color. If you are using generic radiator fluids, it should a bright neon green color. Any variation of browns mean that you need to change your radiator fluid and/or need an engine coolant flush
08-26-08, 09:35 AM
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Just bought a 1993 Lexus es300. It runs pretty good. My only complaint is that the a/c works, but makes the car run hot!!! It's the middle of the summer in North Georgia, and I am burning up!!! Just for good measure, my husband replaced bot the compressor and the dryer--but no luck. The fan will only blow at one speed, causing the engine to overheat. We've been told to replace the hydraulic motor control. Could this be the problem? I've read that these cars should NEVER be allowed to run hot!
AND
The transmission kicks a little too hard for my tastes when going into first gear. Is this common, or the sign of a problem? We plan our first of three fill and drains this weekend.
Just for good measure, my husband replaced bot the compressor and the dryer--but no luck. The fan will only blow at one speed, causing the engine to overheat. We've been told to replace the hydraulic motor control. Could this be the problem? I've read that these cars should NEVER be allowed to run hot!AND
The transmission kicks a little too hard for my tastes when going into first gear. Is this common, or the sign of a problem? We plan our first of three fill and drains this weekend.
A couple of items of note, regarding the A/C and overheating.
• There is a 'cycling switch' that controls the solenoid for the hydraulic cooling fan motor.
I had that switch replaced a couple of months ago. (Fortunately, there is a test that can be performed to see if the switch is bad, or not. Get the manual for your car! The manual for the Toy Camry is the correct book.)
If the solenoid doesn't open, the engine will overheat, because the fan cannot spin fast enough.
• I have read of a connector coming loose on the solenoid, or another part of the cooling system. This causes the fan motor to run, but at one speed only.
Transmission -
• Instead of drain and refill, have the transmission 'flushed'. No matter how many times you drain and refill, you won't get everything.
With a 'flush', the fluid is purged under pressure until it runs clean.
I've seen auto transmissions go bad after drain and refills. Auto transmission fluid is detergent laden.
• A 'harsh' shift is actually better than a 'mushy' shift. Friction is an enemy. When an auto transmission shifts 'silky smooth' there is a lot of friction going on. Personally, I like the trans to shift hard.
My es300 is a '93 also. 111,000 + miles and runs like a new one!
Last edited by byf43; 08-26-08 at 09:41 AM.
08-26-08, 10:14 AM
#4
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1993 Lexus es300 - Engine Overheating
A couple of items of note, regarding the A/C and overheating.
• There is a 'cycling switch' that controls the solenoid for the hydraulic cooling fan motor.
I had that switch replaced a couple of months ago. (Fortunately, there is a test that can be performed to see if the switch is bad, or not. Get the manual for your car! The manual for the Toy Camry is the correct book.)
If the solenoid doesn't open, the engine will overheat, because the fan cannot spin fast enough.
• I have read of a connector coming loose on the solenoid, or another part of the cooling system. This causes the fan motor to run, but at one speed only.
Transmission -
• Instead of drain and refill, have the transmission 'flushed'. No matter how many times you drain and refill, you won't get everything.
With a 'flush', the fluid is purged under pressure until it runs clean.
I've seen auto transmissions go bad after drain and refills. Auto transmission fluid is detergent laden.
• A 'harsh' shift is actually better than a 'mushy' shift. Friction is an enemy. When an auto transmission shifts 'silky smooth' there is a lot of friction going on. Personally, I like the trans to shift hard.
My es300 is a '93 also. 111,000 + miles and runs like a new one!
• There is a 'cycling switch' that controls the solenoid for the hydraulic cooling fan motor.
I had that switch replaced a couple of months ago. (Fortunately, there is a test that can be performed to see if the switch is bad, or not. Get the manual for your car! The manual for the Toy Camry is the correct book.)
If the solenoid doesn't open, the engine will overheat, because the fan cannot spin fast enough.
• I have read of a connector coming loose on the solenoid, or another part of the cooling system. This causes the fan motor to run, but at one speed only.
Transmission -
• Instead of drain and refill, have the transmission 'flushed'. No matter how many times you drain and refill, you won't get everything.
With a 'flush', the fluid is purged under pressure until it runs clean.
I've seen auto transmissions go bad after drain and refills. Auto transmission fluid is detergent laden.
• A 'harsh' shift is actually better than a 'mushy' shift. Friction is an enemy. When an auto transmission shifts 'silky smooth' there is a lot of friction going on. Personally, I like the trans to shift hard.
My es300 is a '93 also. 111,000 + miles and runs like a new one!
If you could give me the technical name for the "cycling switch", I will be forever in your debt!! Is it the cooling fan ecu? Tell me the name and I will buy it TODAY!!!
So, I can go and buy a manual for the 1993 Toyota Camry and it will be the same?!
I've heard and read many, many negative things about "flushing" Lexus trannys. It seems that a three or four cycle of fills and drains do the trick for most people. It's cheaper too!
My Sexy Lexie runs like a dream, too!! Just bought her some new leather seat covers. Just a few kinks to work out, that's all. Finding this forum was a lifesaver. My hubby's mad, though. He's responsible for all the DIY tips I've found so far
08-26-08, 11:10 AM
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If you could give me the technical name for the "cycling switch", I will be forever in your debt!! Is it the cooling fan ecu? Tell me the name and I will buy it TODAY!!!
So, I can go and buy a manual for the 1993 Toyota Camry and it will be the same?!
I've heard and read many, many negative things about "flushing" Lexus trannys. It seems that a three or four cycle of fills and drains do the trick for most people. It's cheaper too!
My Sexy Lexie runs like a dream, too!! Just bought her some new leather seat covers. Just a few kinks to work out, that's all. Finding this forum was a lifesaver. My hubby's mad, though. He's responsible for all the DIY tips I've found so far
So, I can go and buy a manual for the 1993 Toyota Camry and it will be the same?!
I've heard and read many, many negative things about "flushing" Lexus trannys. It seems that a three or four cycle of fills and drains do the trick for most people. It's cheaper too!
My Sexy Lexie runs like a dream, too!! Just bought her some new leather seat covers. Just a few kinks to work out, that's all. Finding this forum was a lifesaver. My hubby's mad, though. He's responsible for all the DIY tips I've found so far
"Cycling Switch" is what the repair shop called it. Sorry, I can't be more specific.
Absolutely, the Toy Camry manual is the same. (The '93 es300 is basically a re-badged Camry . . . . emphasis on 'basically'.)
I had my tranny flushed at 105,000 miles.
It shifts firm and positively. ZERO problems. None.
EDIT: PM inbound!!!!!!!!!!
Last edited by byf43; 08-26-08 at 11:31 AM.
08-26-08, 11:45 AM
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Here's something else to try. . . . . .
Originally Posted by CUMan
Check the connector that plugs into the power steering pump. This connector carries a signal from the fan ECM (under the glove compartment) to the power steering pump. When engine temperature reaches a level where more cooling is needed, this connection causes the power steering pump to increase the cooling fan speed. Higher cooling fan speed is usually needed when the car is idling or moving slowly. Having the AC on would also necessitate more fan speed.
Originally Posted by CUMan
There is a procedure described in the manual (Haynes) where you can check the change in cooling fan speed by bridging two terminals in the cooling fan ECM. When you bridge these terminals, the fan speed should increase. If it does not, you either have a faulty ECM or a problem involving the wiring between the ECM and the power steering pump.
I would first check to make sure the connector is properly attached. It appears that this connector is often detached when power steering and/or engine work is done, and it sometimes does not get reattached. This causes the fan to run at the same speed all the time, regardless of the engine coolant temperature. This causes no problem as long as the car is moving at speed or when the weather is not too hot. But it can really cause a problem on hot days.
I would first check to make sure the connector is properly attached. It appears that this connector is often detached when power steering and/or engine work is done, and it sometimes does not get reattached. This causes the fan to run at the same speed all the time, regardless of the engine coolant temperature. This causes no problem as long as the car is moving at speed or when the weather is not too hot. But it can really cause a problem on hot days.
Last edited by byf43; 08-27-08 at 07:02 AM. Reason: Crediting CUMan with his quote and write-up!
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08-26-08, 09:11 PM
#8
I did the original post which byf43 is quoting above. In describing the method of testing the speed of the cooling fan, I made an error.
The cooling fan ECM is located under the glove compartment; and, as detailed in the previous post, there are several checks that can be made, using a multimeter, to check the ECM operation.
However, the terminal bridging that can be done to check the fan speed IS NOT done at the ECM. This check is done under the hood, on the passenger side of the car. Look for a small black box with "Diagnostic" written on top. The box is about 1" X 4". Looking at the engine compartment from the front, the box is about a foot to the right of the shock absorber mount. The top of this box flips up. Printed on the inside of the top are descriptions of the various terminals inside the box. To check the fan speed, terminals E1 and OP1 should be bridged. According to the manual, the fan should turn at approximately 1100 RPM when these terminals are bridged.
The cooling fan ECM is located under the glove compartment; and, as detailed in the previous post, there are several checks that can be made, using a multimeter, to check the ECM operation.
However, the terminal bridging that can be done to check the fan speed IS NOT done at the ECM. This check is done under the hood, on the passenger side of the car. Look for a small black box with "Diagnostic" written on top. The box is about 1" X 4". Looking at the engine compartment from the front, the box is about a foot to the right of the shock absorber mount. The top of this box flips up. Printed on the inside of the top are descriptions of the various terminals inside the box. To check the fan speed, terminals E1 and OP1 should be bridged. According to the manual, the fan should turn at approximately 1100 RPM when these terminals are bridged.
08-27-08, 05:21 AM
#9
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08-27-08, 05:25 AM
#10
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I did the original post which byf43 is quoting above. In describing the method of testing the speed of the cooling fan, I made an error.
The cooling fan ECM is located under the glove compartment; and, as detailed in the previous post, there are several checks that can be made, using a multimeter, to check the ECM operation.
However, the terminal bridging that can be done to check the fan speed IS NOT done at the ECM. This check is done under the hood, on the passenger side of the car. Look for a small black box with "Diagnostic" written on top. The box is about 1" X 4". Looking at the engine compartment from the front, the box is about a foot to the right of the shock absorber mount. The top of this box flips up. Printed on the inside of the top are descriptions of the various terminals inside the box. To check the fan speed, terminals E1 and OP1 should be bridged. According to the manual, the fan should turn at approximately 1100 RPM when these terminals are bridged.
The cooling fan ECM is located under the glove compartment; and, as detailed in the previous post, there are several checks that can be made, using a multimeter, to check the ECM operation.
However, the terminal bridging that can be done to check the fan speed IS NOT done at the ECM. This check is done under the hood, on the passenger side of the car. Look for a small black box with "Diagnostic" written on top. The box is about 1" X 4". Looking at the engine compartment from the front, the box is about a foot to the right of the shock absorber mount. The top of this box flips up. Printed on the inside of the top are descriptions of the various terminals inside the box. To check the fan speed, terminals E1 and OP1 should be bridged. According to the manual, the fan should turn at approximately 1100 RPM when these terminals are bridged.
Stay tuned
08-27-08, 06:58 AM
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I did the original post which byf43 is quoting above. In describing the method of testing the speed of the cooling fan, I made an error.
The cooling fan ECM is located under the glove compartment; and, as detailed in the previous post, there are several checks that can be made, using a multimeter, to check the ECM operation.
However, the terminal bridging that can be done to check the fan speed IS NOT done at the ECM. This check is done under the hood, on the passenger side of the car. Look for a small black box with "Diagnostic" written on top. The box is about 1" X 4". Looking at the engine compartment from the front, the box is about a foot to the right of the shock absorber mount. The top of this box flips up. Printed on the inside of the top are descriptions of the various terminals inside the box. To check the fan speed, terminals E1 and OP1 should be bridged. According to the manual, the fan should turn at approximately 1100 RPM when these terminals are bridged.
The cooling fan ECM is located under the glove compartment; and, as detailed in the previous post, there are several checks that can be made, using a multimeter, to check the ECM operation.
However, the terminal bridging that can be done to check the fan speed IS NOT done at the ECM. This check is done under the hood, on the passenger side of the car. Look for a small black box with "Diagnostic" written on top. The box is about 1" X 4". Looking at the engine compartment from the front, the box is about a foot to the right of the shock absorber mount. The top of this box flips up. Printed on the inside of the top are descriptions of the various terminals inside the box. To check the fan speed, terminals E1 and OP1 should be bridged. According to the manual, the fan should turn at approximately 1100 RPM when these terminals are bridged.
CUMan,
My apologies for not giving credit, where credit is due!
Your write-up has been most helpful to not only me, but many others!!!!!!!!!
Again, I apologize for not giving you your deserved credit. My post (above) has been edited to give you that credit!
Keith
Last edited by byf43; 08-27-08 at 07:03 AM.
08-27-08, 08:08 AM
#12
The sole reason for my post yesterday was to point out the error I made in the original post.
09-04-08, 04:17 AM
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09-04-08, 10:02 AM
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Help!!!
Well, my husband did the tests you guys recommended and he determined that it is in fact the hydraulic cooling fan solenoid on the power steering pump.
He tested the fan with and without the a/c on, and the speed never changed. Since the cooling fan solenoid controls the temperature of the hydaulic fans, and the fact that it is rusted, we now know that this is the problem! After calling a couple of dealerships, we found out that Lexus does not sell the solenoid by itself--you gotta buy the whole pump--and the dealers prices ranged from $396 to $800
But...we all know the power of the internet
So, I found one for $197 with a $40 core at www.autohausaz.com and it's on the way
.
Stay tuned....
He tested the fan with and without the a/c on, and the speed never changed. Since the cooling fan solenoid controls the temperature of the hydaulic fans, and the fact that it is rusted, we now know that this is the problem! After calling a couple of dealerships, we found out that Lexus does not sell the solenoid by itself--you gotta buy the whole pump--and the dealers prices ranged from $396 to $800
But...we all know the power of the internet
So, I found one for $197 with a $40 core at www.autohausaz.com and it's on the way.Stay tuned....
