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My 1996 Lexus Ls400 Is Leaking Oil!


venmichaels

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So i just purchased a 96 ls400. I test drove it, and everything seemed fine..

This morning when i woke up, I noticed an oil leak....

I cant tell if its oil or power steering fluid..

Sorry Im mechanically inclined... Has anyone experienced anything similar?

Please help..

I feel that I was Ripped off!

What could be wrong with my car??

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It is unusual to hear of an LS400 leaking oil. My guess is that the leak is coming from the power steering pump. That is a very common problem with early LS400s. Usually, the leak comes from the seal between the pump and the reservoir.

If you are not mechanically inclined, you should take your car to a Lexus dealership or independent mechanic for a professional diagnosis. That way, you will not spend money replacing parts that do not need to be replaced trying to find the problem.

If your problem does turn out to be the power steering pump, make sure you fix it immediately. If you wait, it will just turn into a bigger problem. I had a leaking power steering pump in my LS, and I ignored it for a while. It leaked onto the alternator and damaged it, requiring it to be replaced also. Replacing both of them cost about $600, having parts I purchased installed by a local Lexus mechanic.

A remanufactured PS pump with a lifetime warranty costs about $120. Then, you can take it to your mechanic for installation. If you buy the pump yourself, it is much less expensive.

Keep in mind that you do have an 11 year old car. I don't know the mileage, but no car that age is perfect. You could be complaining about much worse things with a different car the same age.

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Welcome to LOC. Thomas is giving you good advice. Nevertheless, It's difficult to advise someone who is not a dyi or familiar with their car. One thing you can do is familiarize yourself with your car. Another is to read up on leaks. There is plenty of information here and it never hurts to be informed when taking your car in for repair. The leak could be anything, from something simple like a loose oil filter to something more complicated like a rear main seal. Determining what's leaking is the first step. Where the leak is coming from is the second step. If your engine is relatively clean, it should be easy to spot. A competent tech should be able to locate the leak fairly easily. Have him show you the source of the leak. If you get an estimate for a huge repair job, get a second opinion or post it here for some honest replies before going ahead with the repair. And if you bought the car from a dealer, you should be able to take the matter up with them. Good luck and let us know how you make out.

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Probably the p/s pump. Smell it and you will now for sure.

Great advice by Thomas and blacktop. These cars aren't ones most people work on themselves but are also cars that don't need a whole lot of work. I think people tend to neglect that no matter what kind of car it is the fluid is all the same and needs to be changed periodically. That keeps the cars happy and adds years of happy driving to the cars life.

I gave our 96 back to my sister with new brake and radiator fluid plus an oil change. P/s was fixed a few months back. All it needs is some new tranny fluid (I replaced that a few years ago) and it will be good to go for many miles.

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So i just purchased a 96 ls400. I test drove it, and everything seemed fine..

This morning when i woke up, I noticed an oil leak....

I cant tell if its oil or power steering fluid..

Sorry Im mechanically inclined... Has anyone experienced anything similar?

Please help..

I feel that I was Ripped off!

What could be wrong with my car??

Ven;

You weren't ripped off. Power Steering leaks are common on these cars. If you can find an Indie that knows Lexus', take it to him. If not, take it to the Stealer and tell him you want the Power Steering Rack Solenoid Screen/Filter cleaned. You should probably have them do a complete P/S flush and fluid replace too. Might cost $200 to $300 high side, but worth it. An honest Indie that knows what he's doing may do it for $150. If you find one, introduce him to mom, you'll want him for your brother.

That screen is the root cause of all problems that manifest themselves as P/S leaks and ultimately, alternator failure.

It's a long story, one that I'm not eager to type again (for the 18th or 20th time....).

Do a search for P/S leaks, solenoid filter, etc. and start following the bread crumbs.

You have a great car, with very few issues or problems. Unfortunately, P/S leaks are one of them. It's an easy fix. Don't let anyone tell you that you need a new rack, new throttle body, new main seal, new cam, new steering wheel, new kidney, new heart, new fingernails, or anything else until you get that little POS screen cleaned and all the crap flushed from the P/S system.

If someone tells you that you have to spend $3,000.00 to make things right......STOP. Come back here & there will be a bunch of guys that will jump in & help you out.

BTW, completely off topic....

A couple of months ago, I went to look @ an '04 430 on a gyppo lot. Nice car, 30'ish K's, everything I wanted, except, of course, the price. I asked the lot rat if I could take it for a drive. He ran inside to talk to the boss, runs back out and says the battery's dead (which it was from sitting so long). He goes on to tell me they've got a battery on order and it's going to arrive in 3 days, because it's a "special" battery and has to come from California.

I couldn't help myself.....I said "Oh, it must be one of those special 12 Volt batteries, huh?

So, I go back three days later and it's all ready to go. So, I pop the hood, look at the (original) battery and say to the lot rat "You know, they carry those special batteries at places like Autozone, don't you"?

It used to be that I'd get really cheesed when I was being lied to..........Now, I don't mind being lied to as much as getting really angry because people think I'm so stupid, I don't know the difference.

Nice car. They wanted $28,888. I was not cooperating. I offered them $24K (generous, given the market conditions). I saw a "fresh" CarFax in the glovebox. It was dated September, 2007. I guess they wanted to hang onto it another 9 months. We parted ways, having failed to successfully conclude the transaction......Sigh, heated seats too.......

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So i just purchased a 96 ls400. I test drove it, and everything seemed fine..

This morning when i woke up, I noticed an oil leak....

I cant tell if its oil or power steering fluid..

Sorry Im mechanically inclined... Has anyone experienced anything similar?

Please help..

I feel that I was Ripped off!

What could be wrong with my car??

Ven:

Oh, and while I'm at it;

Your 1UZFE IS an interference engine.

Be kind to your timing belt. If you don't, and it breaks, your valves and your pistons will kiss and bang their teeth together.......OUCH!

I just thought I'd beat everyone else to the punch while I was here.............

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2nd gen LS dont really have the problem with the leaking PS fluid but its worth checking out.

mine 96 also leaks, but its do to the messed up thread on the oil plug. check yours, i just apply silicone around the plug every time i change oil to prevent the leak

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I agree. I do not think I have ever heard of a LS leaking oil, but I am sure its possible. Neither of my LS400 (my old 90' with 255K, nor my current 91' with 213K) leak/leaked oil (knock on wood).

Like everyone else has said, PS pump leaks are very common however, but not as much on the gen 2 LS models.

Unfortunately, not all Toyotas can get a "rare oil leak" review. The 92-96 Toyota Camrys with the 2.2L had horrible oil seals, as did the 90-93 Toyota Celicas with the same 2.2L. Other than that, those are bullet-proof engines. Not uncommon to see them go 300K+ miles (if you do not see them lock up from being ran out of oil - I have seen it several times on these, but seems to occur more on the Camrys than Celicas - it may be where some Celicas had the 1.6L which I do not think had the problem). My aunt has a 93' Camry LE 4-cyl that she uses as a second car. She has had a mechanic replace the oil seals several times and it still leaks. The car keeps on going and going. She has even ran it so low on oil that the oil warning lamp will illuminate, but it still goes. I think the car is pretty much parked now though and she is pumping in alot of gas into her 2005 Yukon. :rolleyes: I had a 93' Camry LE as well, but mine had the 3.0L V6 (same engine that is used in the Lexus ES300), but they do not have the oil leak problem, but I have heard of headgasket issues on those, but mine had 215K and still ran like new. I loved that car. It was absolutely like brand new in and out. I sold it around 2003 and regretted it ever since.

Ironically, I do not think the same Camrys have a power steering leak issue, but some of the 91-94 Land Cruisers do. Probably the same pump as the LS400. ;)

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I agree. I do not think I have ever heard of a LS leaking oil, but I am sure its possible. Neither of my LS400 (my old 90' with 255K, nor my current 91' with 213K) leak/leaked oil (knock on wood).

Like everyone else has said, PS pump leaks are very common however, but not as much on the gen 2 LS models.

Unfortunately, not all Toyotas can get a "rare oil leak" review. The 92-96 Toyota Camrys with the 2.2L had horrible oil seals, as did the 90-93 Toyota Celicas with the same 2.2L. Other than that, those are bullet-proof engines. Not uncommon to see them go 300K+ miles (if you do not see them lock up from being ran out of oil - I have seen it several times on these, but seems to occur more on the Camrys than Celicas - it may be where some Celicas had the 1.6L which I do not think had the problem). My aunt has a 93' Camry LE 4-cyl that she uses as a second car. She has had a mechanic replace the oil seals several times and it still leaks. The car keeps on going and going. She has even ran it so low on oil that the oil warning lamp will illuminate, but it still goes. I think the car is pretty much parked now though and she is pumping in alot of gas into her 2005 Yukon. :rolleyes: I had a 93' Camry LE as well, but mine had the 3.0L V6 (same engine that is used in the Lexus ES300), but they do not have the oil leak problem, but I have heard of headgasket issues on those, but mine had 215K and still ran like new. I loved that car. It was absolutely like brand new in and out. I sold it around 2003 and regretted it ever since.

Ironically, I do not think the same Camrys have a power steering leak issue, but some of the 91-94 Land Cruisers do. Probably the same pump as the LS400. ;)

False alarm.

I took it to my mechanic who confirmed that it was indeed a powersteering leak..

Its completely destroyed in three places.

I have to get it replaced...

The only main issue now is that it overheats when idle.

Im changing out the thermostat today.

Hopefully it will work!

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False alarm.

I took it to my mechanic who confirmed that it was indeed a powersteering leak..

Its completely destroyed in three places.

I have to get it replaced...

The only main issue now is that it overheats when idle.

Im changing out the thermostat today.

Hopefully it will work!

Ven;

OK, now, what does "completely destroyed in three places" mean, exactly? Get him to elaborate. Don't let him get away with making such a statement without some kind of backup/explanation.

Moving forward, this is where a lot of people have had problems. If you have done any searching on this site for P/S leaks and read the posts, you will see what I mean.

There are two distinct and specific things that need to happen here.

Assuming your mechanic wants to replace your P/S pump, then here is what goes along with that;

Number one is that he MUST, MUST, MUST remove the P/S Rack solenoid, remove the screen/filter from it and CLEAN IT! If your P/S system is leaking fluid, it is because the screen/filter is clogged. That little screen/filter is the root of all your P/S problems. If he doesn't do that, you will continue to have problems and will have fixed nothing.

Number two is that he MUST NOT throw away or "core out" the old P/S pump until you have driven the car for a while (a few days max) to make sure you are satisfied with the steering "feel". Both pumps have what is called a "flow control valve" (FCV) inside of them. It is common for new replacements to have a different "calibration" (if you will) FCV, such that your steering could feel very stiff with the new pump. Because you have kept the old pump, you can take the old FCV out of the old pump and swap it into the new pump to restore the soft, buttery smooth steering we all love so much.

If he gets rid of the old pump and you end up with stiff steering, you're screwed. Don't let him get rid of the old pump until you're satisfied with the steering quality.

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Assuming your mechanic wants to replace your P/S pump, then here is what goes along with that;

Number one is that he MUST, MUST, MUST remove the P/S Rack solenoid, remove the screen/filter from it and CLEAN IT! If your P/S system is leaking fluid, it is because the screen/filter is clogged. That little screen/filter is the root of all your P/S problems. If he doesn't do that, you will continue to have problems and will have fixed nothing.

Number two is that he MUST NOT throw away or "core out" the old P/S pump until you have driven the car for a while (a few days max) to make sure you are satisfied with the steering "feel". Both pumps have what is called a "flow control valve" (FCV) inside of them. It is common for new replacements to have a different "calibration" (if you will) FCV, such that your steering could feel very stiff with the new pump. Because you have kept the old pump, you can take the old FCV out of the old pump and swap it into the new pump to restore the soft, buttery smooth steering we all love so much.

If he gets rid of the old pump and you end up with stiff steering, you're screwed. Don't let him get rid of the old pump until you're satisfied with the steering quality.

A power steering leak can be caused by more things than just the filter. In fact, I think it is probably more likely that the leak is coming from the seal between the pump/reservoir, other gaskets, or Idle Air Control Valve. Those all lose their effectiveness over time, particularly if the power steering fluid was not changed regularly.

I have asked several experienced mechanics at both my local Lexus dealership, and independent shop, about the filter in the steering rack people are always talking about. They all told me the same thing. It doesn't exist. It is just a common myth. The only filter in the system is the screen located at the bottom of the power steering reservoir. During a PS pump replacement, the reservoir comes off the old pump and is installed onto the new one. At that time, this filter should be cleaned.

The only thing that will change the steering feel after a pump replacement is if a mechanic re-uses a worn out Idle Air Control Valve. That part is not contained in the power steering pump. It is sold seperately and costs about $200. My mechanic did not recommend putting the valve back onto the new pump, or buying a replacement valve. Even if it is still functional, it will be oil-soaked and will likely not continue to work for much longer.

Instead, he just bypassed the speed-sensitive steering by installing a bolt on the pump, where the valve would have gone, and capped off the connections for the vacuum lines that used to go to the valve. It does not make a significant change in the steering feel, if any at all. The SC400, with the same engine, is not even equipped with this feature. I do not notice any difference in my car.

If the steering still feels stiff after a PS pump replacement using this method, it is likely that there is air in the system that was not bled correctly.

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Just a quick note as I had the same thing happen to me last year. I noticed an oil leak just inside the driver's side front wheel. It turns out the oil filter was not tightened enough during the last oil change. A simple twist or so and the oil leak was fixed. A bit of a relief I must say.

Good luck,

Eddie

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Assuming your mechanic wants to replace your P/S pump, then here is what goes along with that;

Number one is that he MUST, MUST, MUST remove the P/S Rack solenoid, remove the screen/filter from it and CLEAN IT! If your P/S system is leaking fluid, it is because the screen/filter is clogged. That little screen/filter is the root of all your P/S problems. If he doesn't do that, you will continue to have problems and will have fixed nothing.

Number two is that he MUST NOT throw away or "core out" the old P/S pump until you have driven the car for a while (a few days max) to make sure you are satisfied with the steering "feel". Both pumps have what is called a "flow control valve" (FCV) inside of them. It is common for new replacements to have a different "calibration" (if you will) FCV, such that your steering could feel very stiff with the new pump. Because you have kept the old pump, you can take the old FCV out of the old pump and swap it into the new pump to restore the soft, buttery smooth steering we all love so much.

If he gets rid of the old pump and you end up with stiff steering, you're screwed. Don't let him get rid of the old pump until you're satisfied with the steering quality.

A power steering leak can be caused by more things than just the filter. In fact, I think it is probably more likely that the leak is coming from the seal between the pump/reservoir, other gaskets, or Idle Air Control Valve. Those all lose their effectiveness over time, particularly if the power steering fluid was not changed regularly.

I have asked several experienced mechanics at both my local Lexus dealership, and independent shop, about the filter in the steering rack people are always talking about. They all told me the same thing. It doesn't exist. It is just a common myth. The only filter in the system is the screen located at the bottom of the power steering reservoir. During a PS pump replacement, the reservoir comes off the old pump and is installed onto the new one. At that time, this filter should be cleaned.

The only thing that will change the steering feel after a pump replacement is if a mechanic re-uses a worn out Idle Air Control Valve. That part is not contained in the power steering pump. It is sold seperately and costs about $200. My mechanic did not recommend putting the valve back onto the new pump, or buying a replacement valve. Even if it is still functional, it will be oil-soaked and will likely not continue to work for much longer.

Instead, he just bypassed the speed-sensitive steering by installing a bolt on the pump, where the valve would have gone, and capped off the connections for the vacuum lines that used to go to the valve. It does not make a significant change in the steering feel, if any at all. The SC400, with the same engine, is not even equipped with this feature. I do not notice any difference in my car.

If the steering still feels stiff after a PS pump replacement using this method, it is likely that there is air in the system that was not bled correctly.

Maybe you should show the following to your mechanics;

This Lexus document clearly illustrates the power steering pump and specifically, the flow control valve. It elaborates on the reasoning behind using different letter values of flow control valves.

powersteer.pdf

Pictures and information on the solenoid and screen;

Rack Solenoid

Rack Solenoid Screen

Rack Solenoid Screen 1

A thread started by j.Barleycorn where he does a great job documenting the Power Steering Rack Solenoid operation;

Barleycorn thread

Barleycorn pic's

If you take the time to read the above links, you will find that there is nothing "mythical" about any of it. I assume that because you reference "your mechanics", that you have not personally performed any of this work. Please correct me if I'm wrong.

As I have said in many previous posts, there a lot of people on this board that are more than eager to jump in and help. That is what makes this board great. The majority of those people have done the work, have the experience and share it. In fact, when a board member has the opportunity to help someone else because of his experience, it is very fulfilling. Please be careful not to undermine that.

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Assuming your mechanic wants to replace your P/S pump, then here is what goes along with that;

Number one is that he MUST, MUST, MUST remove the P/S Rack solenoid, remove the screen/filter from it and CLEAN IT! If your P/S system is leaking fluid, it is because the screen/filter is clogged. That little screen/filter is the root of all your P/S problems. If he doesn't do that, you will continue to have problems and will have fixed nothing.

Number two is that he MUST NOT throw away or "core out" the old P/S pump until you have driven the car for a while (a few days max) to make sure you are satisfied with the steering "feel". Both pumps have what is called a "flow control valve" (FCV) inside of them. It is common for new replacements to have a different "calibration" (if you will) FCV, such that your steering could feel very stiff with the new pump. Because you have kept the old pump, you can take the old FCV out of the old pump and swap it into the new pump to restore the soft, buttery smooth steering we all love so much.

If he gets rid of the old pump and you end up with stiff steering, you're screwed. Don't let him get rid of the old pump until you're satisfied with the steering quality.

A power steering leak can be caused by more things than just the filter. In fact, I think it is probably more likely that the leak is coming from the seal between the pump/reservoir, other gaskets, or Idle Air Control Valve. Those all lose their effectiveness over time, particularly if the power steering fluid was not changed regularly.

I have asked several experienced mechanics at both my local Lexus dealership, and independent shop, about the filter in the steering rack people are always talking about. They all told me the same thing. It doesn't exist. It is just a common myth. The only filter in the system is the screen located at the bottom of the power steering reservoir. During a PS pump replacement, the reservoir comes off the old pump and is installed onto the new one. At that time, this filter should be cleaned.

The only thing that will change the steering feel after a pump replacement is if a mechanic re-uses a worn out Idle Air Control Valve. That part is not contained in the power steering pump. It is sold seperately and costs about $200. My mechanic did not recommend putting the valve back onto the new pump, or buying a replacement valve. Even if it is still functional, it will be oil-soaked and will likely not continue to work for much longer.

Instead, he just bypassed the speed-sensitive steering by installing a bolt on the pump, where the valve would have gone, and capped off the connections for the vacuum lines that used to go to the valve. It does not make a significant change in the steering feel, if any at all. The SC400, with the same engine, is not even equipped with this feature. I do not notice any difference in my car.

If the steering still feels stiff after a PS pump replacement using this method, it is likely that there is air in the system that was not bled correctly.

Maybe you should show the following to your mechanics;

This Lexus document clearly illustrates the power steering pump and specifically, the flow control valve. It elaborates on the reasoning behind using different letter values of flow control valves.

powersteer.pdf

Pictures and information on the solenoid and screen;

Rack Solenoid

Rack Solenoid Screen

Rack Solenoid Screen 1

A thread started by j.Barleycorn where he does a great job documenting the Power Steering Rack Solenoid operation;

Barleycorn Solenoid Post

If you take the time to read the above links, you will find that there is nothing "mythical" about any of it. I assume that because you reference "your mechanics", that you have not personally performed any of this work. Please correct me if I'm wrong.

As I have said in many previous posts, there a lot of people on this board that are more than eager to jump in and help. That is what makes this board great. The majority of those people have done the work, have the experience and share it. In fact, when a board member has the opportunity to help someone else because of his experience, it is very fulfilling. Please be careful not to undermine that.

Wow thanks for all the help!

My "mechanic" is my grandfather.

Him and I work on the car together.

I am not much help, Im more of just his assistant handing him tools etc.

He doesnt charge me anything for the work just as long at I buy the parts.

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Assuming your mechanic wants to replace your P/S pump, then here is what goes along with that;

Number one is that he MUST, MUST, MUST remove the P/S Rack solenoid, remove the screen/filter from it and CLEAN IT! If your P/S system is leaking fluid, it is because the screen/filter is clogged. That little screen/filter is the root of all your P/S problems. If he doesn't do that, you will continue to have problems and will have fixed nothing.

Number two is that he MUST NOT throw away or "core out" the old P/S pump until you have driven the car for a while (a few days max) to make sure you are satisfied with the steering "feel". Both pumps have what is called a "flow control valve" (FCV) inside of them. It is common for new replacements to have a different "calibration" (if you will) FCV, such that your steering could feel very stiff with the new pump. Because you have kept the old pump, you can take the old FCV out of the old pump and swap it into the new pump to restore the soft, buttery smooth steering we all love so much.

If he gets rid of the old pump and you end up with stiff steering, you're screwed. Don't let him get rid of the old pump until you're satisfied with the steering quality.

A power steering leak can be caused by more things than just the filter. In fact, I think it is probably more likely that the leak is coming from the seal between the pump/reservoir, other gaskets, or Idle Air Control Valve. Those all lose their effectiveness over time, particularly if the power steering fluid was not changed regularly.

I have asked several experienced mechanics at both my local Lexus dealership, and independent shop, about the filter in the steering rack people are always talking about. They all told me the same thing. It doesn't exist. It is just a common myth. The only filter in the system is the screen located at the bottom of the power steering reservoir. During a PS pump replacement, the reservoir comes off the old pump and is installed onto the new one. At that time, this filter should be cleaned.

The only thing that will change the steering feel after a pump replacement is if a mechanic re-uses a worn out Idle Air Control Valve. That part is not contained in the power steering pump. It is sold seperately and costs about $200. My mechanic did not recommend putting the valve back onto the new pump, or buying a replacement valve. Even if it is still functional, it will be oil-soaked and will likely not continue to work for much longer.

Instead, he just bypassed the speed-sensitive steering by installing a bolt on the pump, where the valve would have gone, and capped off the connections for the vacuum lines that used to go to the valve. It does not make a significant change in the steering feel, if any at all. The SC400, with the same engine, is not even equipped with this feature. I do not notice any difference in my car.

If the steering still feels stiff after a PS pump replacement using this method, it is likely that there is air in the system that was not bled correctly.

Maybe you should show the following to your mechanics;

This Lexus document clearly illustrates the power steering pump and specifically, the flow control valve. It elaborates on the reasoning behind using different letter values of flow control valves.

powersteer.pdf

Pictures and information on the solenoid and screen;

Rack Solenoid

Rack Solenoid Screen

Rack Solenoid Screen 1

A thread started by j.Barleycorn where he does a great job documenting the Power Steering Rack Solenoid operation;

Barleycorn Solenoid Post

If you take the time to read the above links, you will find that there is nothing "mythical" about any of it. I assume that because you reference "your mechanics", that you have not personally performed any of this work. Please correct me if I'm wrong.

As I have said in many previous posts, there a lot of people on this board that are more than eager to jump in and help. That is what makes this board great. The majority of those people have done the work, have the experience and share it. In fact, when a board member has the opportunity to help someone else because of his experience, it is very fulfilling. Please be careful not to undermine that.

Wow thanks for all the help!

My "mechanic" is my grandfather.

Him and I work on the car together.

I am not much help, Im more of just his assistant handing him tools etc.

He doesnt charge me anything for the work just as long at I buy the parts.

Another document that explains the "PPS" or Progressive Power Steering System;

Progressive_Power_Steering.pdf

Take a look at it, a few "light bulbs" may start to "come on"...........Be patient, it takes time.........

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hey i have a 95 ls have the same problem took it to the dealer they said it was the pump so thats my problem

and also the oil pan gasket leaks so could be either the pump is kinda pricy. i put some lucas oil into the resevoir and it stopped the leak thts for the time being u could do that but that has to be replaced will eventually lead to further problems

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