poneyboy

Give it a shot man, there's just a chance that all the reman's will leak & not work. Not sure why... Just something about the powersteering systems in general.

I don't know about Lexus Reman - 600 bills?

LMAO it won't void the warranty. It has a great big TOYOTA imprint on the stamped code on the Lexus rack.

If you're DIY'ing then give the reman Lexus rack a shot. If it's bad you can always take it back.

And mia culpa on the Subaru comment... somewhat kidding.

Yes, the Toyota dealership parts manager said that if you bring it back in, they'll ask for the VIN. If it's a Lexus, they won't warranty it.

To their credit, Lexus did describe why the reman was 2X the others - he said it uses all new parts except the casing. Supposedly none of the others do that? I'm not sure it makes any difference to get brand new parts for all that stuff...

Cheers

Well I don't know. A rack is something I probably wouldn't do reman because they have a bad reputation on other vehicles. (along with reman powersteering pumps). You could maybe save some money on a Camry v6 wagon steering rack, but they use a different ratio so the car will handle alittle different.

I'd personally just buy the new, correct rack & be done with it. And honestly I am the first person to tell you to go back Camry parts if you can do it & it's cheaper.

Racks are cheap but labor can run hella bad on them. Hope you can DIY, or find a really good shop rate.

I hear ya, but I'm a memeber of the "I hate Lexus parts" club. Camry reman = 269, Camry new = 629 Lexus reman = 659, Lexus new = 960. After market reman = same as Camry. But if you buy a Toyota part and put it in a Lexus, you void the warranty! This really frosts my hyde. I'm gettin a Subaru.

Steve

LoL that's why i love playing with Toyota's. "only 160,000 miles on it". lmao.

Ah, I'd stay by checking the steering wheel set nut. I forget what years it was, but that generation they let some ES/Windom/Camry's out with loose nuts. Gives the steering wheel alot of play, but doesn't cause vibrations, etc like say a bad tie-rod would.

Beyond that I would go looking at loose tie rods, intermediate shaft, or steering gear. The rack could be shot. Maybe wheel bearings...

But I'd start with making sure the lock nut is secure lol!

So great to have guys like you on this forum!

Here more what I found: The gear system with hydraulics and all is sliding back and forth as you turn the wheel. I'm guessing a clamp is loose or a grommet is shot. Thoughts? There are signs this has been happening for quite some time but it's reached a level that needs serious attention finally...

Steve

Had a buddy over tonight and we both decided that it needs a new rack. :cries: Unless I can get a bushing for the gear housing... The good news is that racks aren't that expensive. Any reason to buy brand new vs. reman? Dare I admit it?

S

LoL that's why i love playing with Toyota's. "only 160,000 miles on it". lmao.

Ah, I'd stay by checking the steering wheel set nut. I forget what years it was, but that generation they let some ES/Windom/Camry's out with loose nuts. Gives the steering wheel alot of play, but doesn't cause vibrations, etc like say a bad tie-rod would.

Beyond that I would go looking at loose tie rods, intermediate shaft, or steering gear. The rack could be shot. Maybe wheel bearings...

But I'd start with making sure the lock nut is secure lol!

So great to have guys like you on this forum!

Here more what I found: The gear system with hydraulics and all is sliding back and forth as you turn the wheel. I'm guessing a clamp is loose or a grommet is shot. Thoughts? There are signs this has been happening for quite some time but it's reached a level that needs serious attention finally...

Steve

Hi,

Has anyone dealt with this?

I have a 1993 ES300 with only 160k on it and recently, the steering has become rather scarey. It may have been building up over time and I didn't notice it, but it really feels like I'm not getting any steering until late in the turn. I've measured the steering play and while it's a rather subjective measurement, it does seem that it's twice the allowed amount. I'm not sure where to look and the FSM isn't real strong on diagnostics.

- It's plenty easy to steer, so I'm not suspecting the pump.

- When watching the steering shaft as it exits the firewall, there seems to be a good bit of roll back and forth, not sure if it's normal.

- I don't notice any flutter.

- I don't get any shimmy.

Thanks

Steve

ES300, 1993

I see where this has been discussed, but don't see any comparison to my issue yet. My wipers don't work in intermittent mode - at times they default to low speed, at others I get three wipes and a pause, then at other times I get 5 wipes and a pause. It doesn't seem to matter where the switch is set. Mostly, I just get low speed. Also, the wipers don't generally return to resting position every time they are turned off. Depending on where they are in the cycle, they may or may not return.

I seem to recall a friend with a 4 Runner who had similar problems and replacing the motor fixed it. But I'm not sure if his was like this...

Stevo

Virtually all the overheating problems can be traced to owner refusal to keep the cooling system in factory original condition.  Specifically:

1. Owners refuse to use only a 50/50 mix of Toyota Long Life Coolant and distilled water in the system. This prevent radiator leaks from cropping up and eliminates  internal radiator clogging. Also greatly slows deterioration of the radiator hoses / heater hoses / radiator cap / thermostat / water pump / cylinder head gaskets.

Long Life is silicate free - I believe that's it's main claim to fame.  I use 60/50 because it's recommended in hotter climates.  Again, I lost a radiator at 110,000 or whatever it was, not because there wasn't Long Life in it, but because Lexus screwed up a bit on the sizing/manufacturing procedures on my radiator.  There were several of these on the 93.  I always used the "red stuff" and changed it out on a regular basis.  But I lost a pump and radiator.  So what, it's part of the wear and tear.  It's part of living in a hot as hell climate with 90% humidity in the summer that really wears on an engine.  That climate can reduce the cooling system's effeciency a good bit.

2. Owners refuse to use a genuine Toyota radiator cap / thermostat / thermostat gasket / water pump /  hoses / at replacement time.

This is a silly statement.  Genuine or not, replace your caps once a year and inspect hoses.  There is no magic to Toyota hoses - and probably not to their caps either.  Not using genuine parts on every place isn't an issue.  Not keeping up with them is.

Why do owners refuse to maintain the cooling system in factory original condition?  Answer: They don't seem to appreciate the fact they own an ASIAN car and  need to respect and follow the car care advice of the ASIAN car factory engineers (instead of American mechanics, American auto parts stores and American car care websites) if they want  to realize the legendary http://www.saber.net/~monarch/463.jpg reliability and durability potential built into every Toyota.  So they end up butchering up their cooling systems by using (or letting their mechanics use) non Toyota sourced parts, fluids and repair procedures.

This is ludicrous.  Toyota parts are sometimes better, but sometimes just more expensive.  I usually evaluate parts when I buy them and if the Toyota parts look better made, then I buy them.  If not, then I don't.  It's quite simple - there is no magic in it.  What you see is what you get.  And good procedures are not exclusive to Japanese cars.  You state it as if there is some kind of magic Asian formula that will keep a Toyota running longer.  The fact is that Toyotas are built to last and built to take neglect.  Not that you should neglect them, but time and again, treat the two the same way and your Toyota will outlast the American car.  Not only that, the damage you typically see won't be as devastating. 

I would imagine the same problem may occur in Japan. In other words the (obviously few) car owners in Japan who purchase a Ford or Chevy might fail to appreciate the fact they own an AMERICAN car and  need to respect and follow the car care advice of the AMERICAN car factory engineers (instead of Japanese mechanics, Japanese auto parts stores and Japanese car care websites)

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Where do you have a Japanese car parts store? I've never seen one. This is again ludicrous. Good procedures have been established for most vehicles. American makers are adopting some of Toyota, Honda and Nissan's procedures and designs because they are universally good. The big three have made legendary strides in design and engineering and the world recognizes it.

S

I thinks it's not very touchy system. Simply saying your previous engines will run with only 60% coolant and bad components doesn't say much for maintinance history.

I think the changes made by Lexus after the '93 indicate continuous improvement. The fixes they implemented did make the system more robust and fault tolerant. And also, as I mention below, more "mechanic proof."

You miss my point. Like it or not, some cars are very tolerable of cooling system neglect. The 93 ES300 is not as much. This system has multiple points of failure - a point that can't be argued. The frequency of overheating problems when compared to even other Lexus cars indicates this to be so. The tendency for so many mechanics to provide weird fixes indicates the frequency of these events as well.

And yes, 60% coolant doesn't say much for maintenance history - but it also says a lot for the fault tolerance of that vehicle. And it wasn't I who did this to that car...it's the shape I found it in. But I also knew the car and it's record. Like it or not, Toyota has made some poor design decisions.

The simple fact is that no Toyota v6 has overheating problems (Minus a non overheating related blown head gasket) are faults of the owners. Not the engines. If you maintain them, every aspect of them (minus the weak head gaskets during that time frame) will last indefiantely.

You really can't say that. True, very few cars are built today with overheating problems but certain components start failing and the room for error becomes very clear. Now the Jag V12 - that's a car with overheating problems by design. But I agree that this car was not designed to overheat, but it was on the edge and had little room for error - unlike my truck with it's 22R.

Fresh fluid every year and the cooling systems will last 200-300,000. You'll need a new thermostat along the way, but the pumps, radiators and hoses will survive fine on fresh fluid.

You're making this stuff up for the sake of argument. Pumps, radiators and hoses will not survive 300,000 on fresh fluid every year. It's just not in them. Radiators sometimes go that far, but only if you're lucky. Iv'e never had a pump in any car that lasted that long. I've had two Toyotas now and the water pumps went out after about 150,000. It's not an indication of poor maintenance, but an indication of the lifespan of the mechanical seal. That's a proven documented fact - mechanical seals have a finite lifespan.

most mechanics may see that it's not cycling up and down and assume the fan is bad or a bad system.

I completely agree. The hydraulic system sucks because it takes power to drive. Most mechanics hate this style system.

Every system takes power. The fact that you drive an electric fan doesn't indicate that your not using power or that the engine isn't taxed. You're driving a generator/alternator aren't you? Putting a greater load on it will tax the engine more. The hydraulic fan system is great - designed for smooth and quiet operation and a very reliable component. Mechanics see it and don't understand. They don't hear a lot of noise. They think it has to have two speeds. That's why it went away I suspect - dumb mechanics at Lexus. Or perhaps cost. Two electric motors are probably very cheap as opposed to a hydraulic component like that one. The fact is that you can't do better with electric motors. They can't cover as much of the radiator and therefore don't induce as even a flow.

They removed the radiator cap and overflow send->return on the 1mz-fe.

Compair them, they're completely different.

This is a good fix. I agree with Lexus on this one. See the bulletin on the 93 ES300 - they initiated this change.

I know, I just went throuh that problem with a habitually overheating 3vz-fe. Only to find out the original mechanic replaced the 3vz-fe radiator with an OEM '94 1mz-fe radiator. Lowering the boiling temperature 70*F, and not having an overflow return (If a 3vz-fe is overheating, it'll blow the pressure into the over-flow tank, and will suck coolant back into the radiator so there is no air trapped in the system, When 1mz-fe's overheat they blow the coolant out, but air is trapped in the system.)

Again, the replacement radiator for this year ('93) car from Lexus is without a return hose and cap. You don't need that radiator cap or return hose. The air that gets into the system will find its way to the top and can be bled out through the engine cap/return hose. You don't need the radiator return hose/cap - it's just another point of failure - Lexus knew this and changed it. (However, I went out and bought an aftermarket radiator that does have the return hose. No, sorry, can't justify the $699 they quoted me for a plastic Lexus radiator. I like my aftermarket model better. )

I troubleshot a 1mz-fe last week who's waterpump was completely corroded off.

(Pay attention and you'll see why this is actually common by the end)

The guy had the radiator replaced when the plastic top sprang a pin-hole leak (high pressure + low flow + nasty corrotion from bad fluid = bad). The leaking coolant was fixed, but the car was still overheating. Normally you would ask why?

Because the water pump was corroded off! Most of the time, if you have left old fluid in long enough to blow the stock radiators, there will be some degree of pump damage. (Maybe that's why Toyota has always used plastic radiators.)

^ That's how the pumps get damaged. That is always why any *good* Toyota mechanic will tell you when the radiator is replaced, the pump may or may not be shot also.

Corroded where? You mean the impellor? That's just bad maintenance. Worn water pumps are not typical with this car or most other Toyotas. If they are abused as you indicate, then that can happen - with any car. I typically see the water pump lose it's mechanical seal before it corrodes. This is typical Toyota behaviour that I've noticed over the past 20 years. In fact, I've never personally seen a worn pump impellor on any of my cars - only heard about them! Long Life coolant is supposed increase the lifespan of the pump seals. Perhaps this is true, but not on my '93.

For refferance, anytime any of your hear about a radiator blowing, or leaking. The entire system needs to be flushed for a long time to clear the corrotion & sludge, and the pressure needs to be tested when the enigne is warmed up to insure the pump is not damaged.

(VZ-FE owners don't fret because you're coolant is not comming clean... The blocks are iron, and the water will ALWAYS come out orange/rusty looking LoL!)

This is a little odd. I don't see how a pure and clean flush can't come clean in the end - mine does and I have the iron block. Maybe you need to find that petcock. However, I disagree somewhat on the radiator always indicating a bad pump. My radiator was very thin and quite frankly a very weak link. The later one was much thicker and heftier. I believe this was a mistake on Lexus' part and one of the many reasons this car ran into so many overheating problems. It couldn't take the heat very well so developed hairline cracks, and it was simply too small. Poor choice by Lexus. Good choice to come up with a new one...

You're pretty much dead on tho. If people would replace the water pump on schedule, and keep fresh coolant in the system (drain the radiator every year, or flush the system every other) You'll simply never have a cooling problem.

I have to add - keep those hoses and caps inspected.

sux you have to go through this but this is my 2 cents worth...

call Lexus customer service...i did, and they made my dealer (who thought i was crazy for having condensation in my headlamp) replace the $500+ labor part the next day!

Lexus wants to win the HD Power award again for the what is it- 16 th straight year? they will do whatever it takes to make you happy, even a CPO. Mine is a cpo.

Document everything, like a diary, and offer to email/fax/mail it to the customer service rep.

Be respectful and mindful that the rep you are speaking to did not belittle you, he is the one who will help you.remember, you called him for help.

Don't give up...if you believe you are wronged let them know.

I stopped dealing with the disrespectful service reps at Lexus of Westport in Fairfield, Conn because they gave me the same feeling you described above.

We paid a lot of money for our cars, new or not, and it's our right to be treated with the utmost respect.

I look extremely young for 34 and when I used to go in there in shorts and a ball cap- the service reps did not even acknowledge me.

They lost my business right then and there and i tell everyone i know not to go back there.

they also lost a sale as I will upgrade and get a 430, but from another dealer.

Bottom line is this...Lexus needs to know how poorly some of us have been treated. I believe they do take it seriously, as evident by the call i received from the dealer 24 hrs after i called customer service- the dealer said "can you bring in the car today?".

it's too bad we have to resort to calling customer service, but i'm afraid how other manufacturer's handle their clients.

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You and I are in agreement. I have noticed that Infinity dealers in my area are pretty freindly and helpful. I've also noticed that Lexus service centers are either incompetent or jerks. This is very sad. We aren't buying Yugos here...

Stevo

The cooling system is not delicate if the owner takes proper maintenance. The system is no worse than any other good cooling system.

Many times the problem happens from correction, and sludge buildup. Old fluid is bad to clog the radiator, and corrode the pump fins.

I disagree. This is a very touchy system. I've owned cars that could go with only 60% of their coolant and corroded radiators and still run like a champ. Most cars are more forgiving than this one.

The pump fins will not corrode before the pump seal goes. You will see yourself replacing leaky pumps before you will see a corroded impeller. If you have a corrosion problem, the pump will leak first. Hence my point that it's not a solution to overheating. If your overheating is because you don't notice the water dripping from your pump, yes it is the fix. But when you have the symptoms that most of us have been scratching our heads over, then the pump won't fix it.

Youa re very correct that the hydraulic fan system doesn't wear out (itself) Typically the problems that arise with it are:

1) burned fuse

2) the connector from the Cooling fan ECU to the Cooling fan clutch (what controls it's high-low speed) is not plugged in.

3) something shorted and destroyed the cooling fan ECU ($5 part in a junkyard)

Cooling fan clutch? I think you mean a solenoid or better - butterfly valve. It is a continuously variable system with no real discreet speed settings.

It can be checked by jumping E1 and OP1. If the fan does not go into high speed, there is a cooling fan problem.

This is correct. My point here is that most mechanics may see that it's not cycling up and down and assume the fan is bad or a bad system. Jumpering the circuit will prove that your fan is fine.

The water pumps last a very long time, if you keep good fluid in them and skip their replacement every other timing belt change. Normally that is not worth it, they only cost $75 with no extra labor charge. You can also easily corrode the fins off one (loosing pressure) by having poor fluid in them.

Again, not at all very likely. You will have other more serious problems long before you corrode your impeller fins - like a leak.

A common problem with fluid boiling over is worn pressure caps. That is common to all cars, not just that particular engine. Also the reason why you can't use a 1mz-fe radiator on a 3vz-fe. The 3vz-fe has the over-flow returns, and a pressure cap.

A pressure cap will raise the temperature before the coolant boils 40-70*F. If one is malfunctioning, or worn, it will cause many such problems.

A slight correction here - the new radiator for this year car has no cap and no return hose. The reason is obvious - remove another relatively unnecessary point of failure. In fact, it's not common anymore as many many cars have gone away from caps altogether - all caps. It's much much more common in this car as there are two caps with return hoses as well as a petcock on the radiator. Hence their tendency to overheat more than other cars - many many points of failure.

Steve

Make the dealer fix it. This behaviour is inexusable and Mr. Toyoda would be horrified. Lexus and Toyota dealers are notoriusly arrogant and condescending. Here's my experience:

I walked out of the dealer with Toyota Long Life under my arm and asked a service manager "Can you tell me where I should look for the coolant petcock under my engine so I can drain it out completely?"

His answer was "We don't do that, we remove the hoses and that gets it all. That hose is the lowest point in the engine."

I said "That's funny, none of my hoses are that low. I would end up with very little control over my mix if I do that. Besides, I have a petcock on my radiator that is very low, but not low enough."

He asks a mechanic who is walking by. He gave me two possible locations and indicated that he does in fact use this to drain the systems. He was right.

My Lexus service manager was a nice guy, but incompetent. He quoted me $700 to resurface my brakes. This didn't include bleeding the system. However he did say it included relubing the bearings. Funny thing, my bearings are sealed ball bearings.

Go get 'em. Go to the top guy and/or write a letter if you have to. They are clearly being pricks and you are not out of line. Explain that you will be helping them learn about a problem they are likely to see in the future!

Steve

ES300 Overheating Guide

OK all, this is an attempt to sum up several experiences I've had with my ES300 and it's overheating problems and hopefully decrease the pain that everyone is feeling when this happens:

What happened to me:

1) Had a leaky radiator a year ago that was letting air into the system but not leaking coolant when under pressure. So I had this intermittent boil over issue that would crop up from time to time. When it was finally obvious, I replaced the radiator and it ran great - for a while.

2) I had leaky radiator caps that were also letting air in. So if I topped off the system and drove around, everything was fine. After a day or two, air was getting in and I would have an intermittent boil over - but only so often. Replaced them and it did well for a while.

3) Recently, I had a more consistent elevated temp issue. This was happening after 15 minutes on the highway on hot humid days. When I pulled into my driveway, the temp would jump up slightly. Plus, there was a lot of bubbling into the resevoir, so I thought there was air getting blown into the system from a blown head gasket. Decided to find that damn petcock and completely drain the system and replace the thermostat before I went for a head gasket.

Low and behold, I found an old gasket that had been melted to the inside wall of the thermostat housing. It was dangling over the thermostat and possibly jamming it's operation. I removed this and replaced the theromstat thinking I was ok.

Well, it heated up again. This time it was in my parking lot at work the next day. Opened the hood and the heater hose had blown a pin hole. Hmmm - thought for sure I had a blown head gasket now. Replaced the hose and limped home.

Funny thing, the bugger behaves pefectly. Instead of stopping in the driveway and finding the temp goes up, it actually adjusts down slightly. This indicates that the flow is greatly improved. So I think that hose was balooning and messing with the ability to create enough pressure in the system. It may also have become gas permeable and been allowing air into the system as it cooled.

Now, with all this, it has become clear that the cooling system in this car is very delicate and requires that every element be working perfectly. It is also clear that it can take a tremendous amount of punishement before needing a new head gasket. Given all the stories of head gasket problems and hydraulic fans being replaced by electric ones (this NEVER solves the problem folks, it's just not a part that breaks), I can only conclude that there are a lot of rich mechanics out there who don't understand this thing or there are a lot of poor owners out there who have been duped.

I looked into this and here are several fixes that have been used (my own car history indicates that someone was throwing parts at the car).

What not to do:

1) :chairshot: Replace the hydraulic fan with electric ones. This fan doesn't break. This is not a solution and don't let any mechanic tell you otherwise. Again, this fan doesn't break. You may need to replace the filter and/or the fluid, but this thing is rock solid. Two electric motors will not be able to move as much air as that original fan, and they will never work right. It's a gerry rig at best and may only mask your real issues.

Why the hydraulic fans? To decrease fan noise. Why not replace it? Because it always looks bad and because it doesn't really solve the problem. Mechanics see it and think it is a design flaw. In reality, you may only need to replace a solenoid or something like that to improve it's operation.

2) :chairshot: Replace the whole hydraulic system. It's been done, but it doesn't help. Again, they are throwing parts at you. Only if the pump is making noise and obviously broken do you need this. The assumption is again related to the fan. Mechanics see that hydraulic fan and always assume it's the problem when in reality it's the one element in the system that is not likely to break.

3) Replace the water pump. This isn't a solution to the overheating. Don't do this unless you have a leak or you are replacing your timing belt. These water pumps don't last long enough to wear out impellors. If this is your mechanic's solution to the problem, he doesn't really know what's up. There is no good way to test flow in this system anyhow, so how could he know?

4) Replace a head gasket. This may be your problem - but if your trouble is intermittent, don't go for it unless you have irrefutable proof. These things are pretty solid and can take some serious punishment. I may still have to do this on mine, but every time I'm worried about it, something else manifests itself.

5) Remove the thermostat. This can help, or it can make things worse. I'm not sure if it's a bad thing to do when it makes the overheating stop. But it's only masking the real problem. In some cases, this actually increases your temperature by increasing the flow too much and not allowing enough heat exchange through the radiator. In other cases, it really stops the overheating. It could be a stop gap measure, so I wouldn't rule it out. Just realize it's only that.

So in case it's not been obious, here are the legitimate fixes:

What to do:

1) Make sure you have good caps. These are critical

2) Make sure you properly fill the system from the top fill point. Let out all air as you do. I have posted the proper procedure previously. Do not assume the air will find it's way out!

3) Make sure all your hoses are in johnny !Removed!&span condition. This includes your overflow hoses that run to the resevoir as well as your upper heater hose.

4) Make sure your thermostat is good. It's rarely the problem, but not expensive as a rule-out step.

5) When you bleed and re-fill the system, use the petcock on the back of the block to get it all out. And refill with Toyota long life. Your water pump will thank you for that.

6) Make sure your radiator is good. If it has any small cracks or signs of wear, it may be your problem.

7) Get really good advice and be very certain if you suspect a blown head gasket. It's risky to drive it if you do have one, but also very painful to replace it and find out it's not your problem! In many cases, the head gasket is impossible to diagnose if your problem is intermittent.

Sorry for the long post, but I was hoping this could help someone out there. The 93 and similar ES300s have very solid motors and are worth fixing. So be patient and don't let a mechanic quote you $2500 for a new head gasket set when you can buy a very nicely rebuilt motor for $1795 and pop it in yourself for nothing. Or better yet, do your own head gasket for under $400. And make sure that's your problem!

Ciao

Stevo

Thanks Bartkat, you've basically told me what I wanted to know. I loathe working on Hond Civics. And it seems that they've gotten more crowded under the hood.

Hi all,

I'm usually in the ES300 group, but I'm seriously thinking about one of these IS300s and was wondering if you folks find it relatively easy to work on? Or do most of you folks take the car to a dealer? I tend to do my own work to save money and make sure the work is done right. Rarely will my cars go to a dealer and when they have to, I'm always nervous that it won't be treated properly.

-S

Hi,

I have a 93 ES300 and it has to be the best finish I've seen on any car. Most people think it's brand new. So whatever dealer said that it's a problem with all Lexus cars is full of it. It looks like you guys are up for a helluva fight, and don't quit - I want to buy one of those IS300s in a couple of years, so make sure you get them to fix your cars!

Also try www.carpoint.com. Some of the mechanical reviews can tell you what goes wrong with a particular car.

So for 250 it's a deal.

My dealership quoted around $600, don't know what a 3rd party would be. This is why I'm doing it myself soon.

Lexus pads also squeal. The only things you can do is get your rotors turned and put on new pads that don't squeal as much.

Chances are, its your valves and they need adjusting. Yes, dealerships will charge you a *BLEEP*load of money for this very simple task. Try a trusted independent mechanic.

Thanks for the response.

So in this case, I'm talking about damage from overheating, especially when you don't get a blown head gasket. It seems that a serious overheat can cause problems down the road. What problems are they? How do I know if I have them?

I've never heard of valves being out of sync...you must mean clearances. But this doesn't constitute heat damage I wouldn't think. Mostly I'm thinking of possible things such as cylinder damage and such. Perhaps rings fall into that category.

For the record - when it comes to valve clearances and other scheduled maintenance items, it seems that Lexus dealerships are not in the habit of doing any of these important measures. I don't trust them.

93 ES300, 105k

Anyone know what signs to look for with regard to heat damage? I have a co-worker who had a GMC truck that overheated once. It didn't blow a head gasket, but a year later it died from the heat damage. He said it started sounding more and more like a diesel until it guit running. Any ideas here?

It sounds like you have the 93 like I do. I've been through the exact same thing as you - water pump, radiator, etc. etc. The overheating problem is intermittant. I haven't replaced anything in the power steering system yet, but supposedly there is an actuator switch that turns on the flow to the fan motor. (It's a hydraulic fan that runs from power steering fluid pressure) Ask your mechanic if he replaced that - it's the only thing in your power steering system that should be considered when related to your cooling system.

I wish I could help you, but I'm beginning to come to a conclusion: if fixing the power steering actuator and heat temperature switch doesn't help, then this car is destined to overheat! It seems that it was inherently designed with a poor cooling system. This is certainly why they went to the standard electric motor the following year! Perhaps there's a mod that will allow for an electric fan motor?

I'm hoping we have some guys here that can help. I just had to replace my radiator, but before that it was my water pump. I have a new thermostat and new caps. The radiator and pump were in need of replacement, but still I have some cooling issues. I believe it's the cooling fan system - the hydraulic one. I assume there is a temperature sensor and an actuator that work together to make this thing work.

Does anyone know how this thing works and how to go about troubleshooting this fan? It seems to be the issue as I find intermittent increases in temperature when stopped. At times, it works flawlessly and stays below the half mark. Other times, it creeps up to the next tick mark - and I fear it will overheat. Once I get going, it comes back down. I also think there may be two speeds to this fan?

It just may be that the fan switch is the real bugger in this whole equation - at first it appeared that my woes were over. But now it appears to be back. Possibly the new and bigger radiator is preventing a quick oveheat, but I don't trust what's going on.