Power Steering Issues

I am experiencing intermittent power assist with the steering in my 1998 T&C. Sometimes the steering will work just fine. At other times, though, I will feel a pulsing vibration in the steering wheel, while idling at a stop light. When I turn the wheel, the effort needed will pulse with the vibration. During the last 3/4 of a turn to either lock, the power assist will disappear (max steering effort from me required). Then, suddenly, the vibration will disappear and no problems, full assist from lock to lock.

This condition began about six weeks after taking the van to the Chrysler Dealer and having them replace a weak belt tensioner with one I purchased separately and brought to them. At the start of this condition, I checked the PS fluid. I was slightly low, but within range, except there was a blob of oily sludge on the end of the plastic dipstick, the portion of the stick that remained submerged in the fluid during normal driving. I had to scrape this stuff off since it wouldn't wipe off with a cloth.

This is the second problem to develop after going to the dealer. Three weeks after the dealer, the idler pulley mysteriously unbolted itself, causing the serp belt to shread. Fortunately my wife was one block from the house when she lost the power steering and the engine overheated. Naturally the van has a new serp belt and idler pulley, which I installed myself. This incident was especially strange since I replaced the last idler pulley myself and tightened the bolt correctly only one year before.

All this makes me wonder, is there some type of additive that an unethical mechanic could add to the power steering fluid, that would make it coagulate into sludge and gum up the pump? I am going to flush the PS system at my next weekend opportunity to see if this corrects the problem. Anybody out there have a similar experience or have any insight on this?

All this is starting to tax my sanity. Everytime the power steering burps now my wife screams "the power steering is going out!". It didn't help when last night, the ABS light stayed on after she started the van. This is the one and only time to my knowledge that the ABS system didn't pass it's self diagnostic on startup in the last seven years. I had her restart the van and the light went out. No problem since. I'm just waiting for her to declare the van unsafe to drive, which I know darn well it isn't. Thanks for letting me vent.

There is a screen in the bottom of the power steering resevour that gets clogged up with the same goop you found on dipstick.
Suck it out and clean screen, replace fluid with ATF4 only.
Also check the power steering hoses for recall, some of them burst, then the van catches on fire if engine is on and all warmed up.

Thank you for the response. When you say reservior, I assume you mean the fluid chamber mounted on the side wall, the one with the cap and dip stick. What do you use to suck it out? Also, what about the fluid in the pump and rack? I would expect there to be some gunk in those places as well. Anyway, I will keep you all posted once I get time to mess with it. Not a critical situation now, just a nuisense.

KManiac,
When you do flush the system, I really recommend that you only put in fluid that you get at the dealer. After 4 failed PS pumps, one failed rack and pinion my OLDS works great. I think it was that it was really sensitive to the generic fluid that I was putting into it. It cost me a fortune.

Best Regards,
Stan

Well, I dug into the power steering today. I took a vacuum pump with an intermediate container to suck the fluid out of the upper reservoir. Then I removed the plastic reservoir and ran a tube down the filler hose to suck the fluid out of the pump. What I found in the fluid were small chuncks of the black, rubbery substance I described in my earlier post, plus clear globs of something thick that resembled petrolium jelly.

Now for the plastic reservoir. There was no screen inside of it. What I did find was that the bottom of the reservoir, as well as the sides up to the top of the fluid level was coated with a layer of the black, rubbery substance I mentioned previously. This gunk stuck to the plastic tank like glue. I had to use a long, narrow, flat blade screwdriver to scrape what I could off the bottom of the tank. Spraying it with brake cleaning solvent had no effect. This stuff likes to stick to itself, but will not stick to skin or my latex gloves. I have never seen anything like this before.

Anyway, I refilled the system, started the van, turned the wheel back and forth several time, the drained the pump again with the vacuum pump. I put the plastic reservoir back in and refilled the system. There doesn't appear to be a problem with the steering as long as the van is moving. However, when sitting still, the system will lose a portion of the power assist at the last half turn before either lock.

My problem appears to be chuncks of this black, rubbery substance floating through the system. I think it gums up the pump and valving, causing the erractic operation of the power assist. Does anybody out there have the slightest idea what might cause the formation of this junk? Could it be that the dealer mechanic spiked my power steering fluid with some type of contaminant in an effort to make me bring it back for more service? I am awfully paranoid about this.

Any input on this subject would be greatly appreciated. For now, we will drive it the way it is until it either gets better on its own or it gets worse.

This may be an option to look into: http://planet.tvi.edu/bpearce/1995Lincoln/PwrStrFlsh/Index.htm I've heard nothing but good comments about SeaFoam products.

There are several companies out there that make a liquid flush solvent just for that purpose. I'm considering one because I've been toying with a noisy pump lately. I've removed the reservoir and cleaned the back crud off the sides. It was just black, not rubbery and didn't see any chunks. I have since drained the res again and replaced the fluid trying to get more fresh fluid in the system but, the noise persists.

It's possible that brake fluid or a foreign additive was added to the PS system at some point and the seals are now wasting away. I don't know if a technician would consciously do this for return business.

For peace of mind, I'd replace the rack, pump, and hoses myself for about $250.

Well, at this point there are no leaks with the system. Just that intermittent loss of power assist at the extreme points. I have considered replacing the entire sytem, but I will wait for more conclusive symptoms of component failure before I do.

I thought of doing the work myself. But when I crawled underneath it, I was amazed at how much stuff is jammed into the space under the hood. It appears that I would have to drop out the exhaust system, right half shaft and AWD PTU before I could get enough clearance to even SEE to the power steering pump and hose connections from underneath, let alone put a wrench on any of it.

My other Chryslers may be old, but at least I don't have to disassemble half the car to work on the engine.