1999 Chrysler LHS mystery component using fluid

I'm confused. Is the fluid on the passenger side or by the pedals? Sounds like the spool valve seal is leaking. It's at the end of the steering column next to the firewall. Parts are not available; you will need a rebuilt rack and pinion assembly and an alignment. Fortunately, remanufactured assemblies aren't very expensive compared to new ones.

Caradiodoc

The spool valve is the valve assembly the steering shaft turns. It's in the rack and pinion assembly, and directs pressurized fluid flow to one side of the power piston or the other side to push the steering linkage in one direction or the other. This is not a common failure, so a salvage yard part isn't a bad option.

As a suspension and alignment technician, I replaced a lot of racks, but I only saw one other spool valve problem on a Chrysler product. That was on my mother's '95 Grand Caravan. It didn't leak, but it did the other things you described. GM had a real lot of trouble on their front wheel drive cars in the past. Chrysler, ... Not so much.

You might want to check into the cost of a remanufactured unit before heading to the salvage yard. Cost has come down a lot and many have improvements built in by the rebuilders.

Caradiodoc

In the 1980s, GM had a real lot of trouble with "morning sickness" with their front wheel drive cars. The symptom was lack of power assist in only ONE direction first thing in the morning. This would last from half a minute to many minutes until the fluid warmed up. Eventually the other direction would also be affected. The problem was caused by internal leakage of the highly pressurized fluid.

GM's fix for this problem was to replace the spool valve which included new seals. It was designed to get the car out of the 50,000 mile warranty. What happened after that, they didn't care. Very poor business practices as this is no way to look out for their customers. Yes, the new seals solved the problem, but everyone but the customer knew it wasn't a permanent fix.

The real cause of the problem was as the seals rotated when turning the steering wheel, they wore grooves into the soft aluminum housing. The grooves were causing the fluid leakage, not the seals. The old seals were worn just a very little bit, not enough to cause a problem on their own, so the new seals on the new spool valve were just big enough to seal for a few more miles. All GM wanted was for it to last another 10 - 15,000 miles to get the car out of waranty. After that, when the problem occurred again, the customer had to pay for repairs. Of course, then it was diagnosed correctly as needing the entire rack and pinion assembly. New spool valves and seals are not available for individual replacement anyway.

There was a 100 percent failure rate on GM front wheel drive cars, and a 100 percent second failure rate on those that received the new spool valves under warranty. Chrysler never had this problem other than the normal sporadic failure here and there, yet when any rack and pinion assembly is rebuilt, they receive the same treatment as the GM units.

Two aftermarket companies, Moog and Federal Mogul, in particular, bore out the aluminum housing with its grooves, then press in a stainless steel insert. The hard steel tube and the teflon-coated sealing rings will last forever. GM rack and pinion units in the salvage yards are sure to be remanufactured units with this modification, so the chances of getting one with a problem is low. It is very possible with a Chrysler rack to find an original that never developed a problem. My 1988 Grand Caravan has 217,000 miles and the rack is original. In fact, I've only replaced one $32.00 outer tie rod end so far in the entire steering and suspension system.

One common problem with Intrepid rack and pinions was squawking mounting bushings. They are riveted to the rack housing with rubber isolators in between. The rubber could dry out causing a noise when they flexed under the high pressure of turning the wheels. There were no repair parts available from Chrysler, and it wasn't a safety issue, just annoying. Spray lubricants would solve the noise for up to a few weeks, but the permanent fix was to replace the entire assembly. I don't know for sure, but I would bet the aftermarket rebuilders have come up with a solution. Aftermarket companies are real good at solving common problems like this, and their prices are not bad. That's why I suggested a rebuilt unit might be a better alternative for you if you plan on keeping the car. I still wouldn't be worried about using a salvage yard part, but you might be surprised at the little difference in price. Many rebuilt racks have lifetime warranties too although that would just cover the part, not the labor to replace it or for the alignment.

Caradiodoc

Something doesn't seem right. The wrong fluid should not cause a new seal to leak or pressures to go too high. I wonder if there was some other problem that was overlooked.

If there is a variable assist valve screwed in near where the hoses connect, unplug its electrical connector and see if the power assist comes back.

Caradiodoc

There are two possible approaches but both require a trip to the dealer. One step is to connect a pressure gauge between the pump and rack. A valve is closed momentarily to see how much pressure the pump is capable of producing. It should hit at least 1100 psi. If it can not, the pump is worn and must be replaced. Next, the pressure is observed when the valve is open but the steering wheel is not being turned. Pressure should remain very high. If it drops real low, internal leakage is taking place in the rack.

In nine years as a steering, suspension, and alignment specialist at a very nice family-owned Chrysler dealership, I only used that tool once, on an Intrepid from out-of-state. I can't remember what normal pressure was with the valve open, and I never did find the cause of low power assist because the owner had to head home. I DO know a new rack and pinion and a new pump did not solve the problem. All that left were the hoses and the variable assist valve and control module.

Your second step, the one I didn't get to, would be to use the Chrysler hand-held computer to access that variable assist module and operate it remotely to see if it responds. It is actually listed in a sub-menu under Automatic Transmission. Vehicle speed data from the transmission computer is one of the inputs to the variable assist module so it knows to provide more power assist at low speeds. This system caused so little trouble, I only remember replacing a few racks over the years. There are no common problems I can think of.

Caradiodoc

? I know there is a clue there, but I'm not sure how to interpret it. Is it possible the hoses are mixed up? With every rack I ever changed, the two hoses were different sizes, but something weird is going on here. Perhaps the solenoid needs to have voltage applied instead of being unpluged. The module could be defective too. It is plugged onto the driver's side of the rack assembly. I never had to replace one. I don't even know if they are capable of setting diagnostic fault codes. Kind of strange that in nine years as a specialist at a dealership, I only ran into this problem once.

The pressure gauge is a specialty tool, but it only works when the fluid flow can be stopped with the included valve.

You're right about seeing the dealer so they can use their computer. I have their older DRB2 and the newer DRB3. They will do everything necessary on Chrysler products. The newer model will even do emissions-related stuff on any brand of car sold in the U.S. Since 1996. A few independent shops also have the Chrysler computer, but it costs so much to buy the specialty equipment for every brand of car, so most shops use aftermarket equipment that works on many brands. It is still real expensive to update the computers every year, but it's not as bad as updating equipment from 30 different manufacturers every year. The downside is the generic aftermarket stuff never is capable of doing everything the manufacturer's equipment will do. By law, manufacturers must make their emissions-related data available to everyone. The other stuff, like the body controller, transmission controller, air bag computer, and especially the anti-lock brake computer can take years before they can access those computers because they have to reverse-engineer the cars to figure out the circuits. The aftermarket equipment is getting a lot better the past few years, but it will never equal the manufacturer's equipment.

I don't think the variable assist valve is stuck because the steering is easy until the engine is started. That is a clue that should be mentioned to the mechanic.

Caradiodoc

Those tubes are not something we ever take off in the field so I don't know if they can easily be mixed up. They transfer the pressurized fluid to one side of the power piston to push the steering linkage. When the linkage moves, it closes the valve unless you turn the steering wheel further, otherwise it would continue turning if you just held the steering wheel off-center. It would seem to me the piston would move the wheels in the opposite direction you are turning the steering wheel, so the valve would never close and the steering would go quickly to a full turn. Anything is possible, but I don't think the tubes are mixed up. I think you'd have some pretty wild symptoms, and the people who rebuild these units have been doing it a long time. They know what they're doing, ... I hope.

Caradiodoc

Can't say I ever watched the level in the reservoir, but if it is changing, that would suggest there is still air in the system someplace and it is compressing. The fluid has to go someplace when the level goes down and it has to come from someplace when it goes up in the reservoir. It's either that or the high pressure hose is expanding which isn't likely.

Caradiodoc

The spool valve you're referring to is a two-piece unit that doesn't care what its position is when it comes to opening and closing ports to direct fluid, but you're right, it will make the steering wheel off-center. You aren't likely to notice if it's off one or two teeth because during the alignment, the final step is to hold the steering wheel straight with a fixture, then adjust each front wheel to straight ahead. You will have a straight steering wheel when driving, but the steering wheel would turn a different amount for full left and full right. It would affect the turning diameter but nothing else.

Next, I would use a pair of small jumper wires and apply battery voltage to the solenoid to see if the steering gets easier. If it does, that would imply the small module clipped to the driver's side of the rack isn't working, or it is not getting the signal to do its job. At that point I would have to do some more reading, but since the diagnostic testing with the factory scanner is accessed under "transmission computer", I would assume that's where the signal is supposed to be coming from. I was only involved once with this problem, and after replacing all the same parts you did, he had to go home about five states away, so I never did find out what the problem was.

Caradiodoc

Well, at least in the future I'll know to not look at the pump and hoses. I agree it would be nice to know the cause of the problem, but happy you have power steering again.

Caradiodoc