Bad problem with jerky steering - any feedback?

I hope some people reading this will have helpful advice on what may be causing a long-standing problem on my 1986 Camry.

On 3/19/04, my engine had stopped on me, and I had it towed to a shop for repair. On 3/23, the shop worked on it and replaced the timing belt, an idler pulley and tensioner. I was able to drive the car again, and did.

However, on the day after the repair, I noticed a new problem: the car would now suddenly and abruptly jerk to the left on increasing speed for just an instant; and it on increasing speed, it would, with a little less force, abruptly jerk to the right on falling speed. It was most noticeable in the

60-70 mph range (not surprising because friction with the road is less at higher speeds), but also at lower speed ranges, too.

I suspected something was wrong with the power steering; however, othing was really apparent. I thought perhaps the shop had inadvertently done some damage to the pump during the timing belt replacement somehow; the pump has to be either swiveled aside and "unbelted" (for lack of a better word) or removed to replace the timing belt. However, I did nothing about the problem. There was and never has been any sign of power steering fluid leaking anywhere.

Last spring or summer, I posted a message here explaining my problem, and I was told that "torque steer", a frequent problem on front wheel drive cars, might be my problem. The responses I got at that time, and the literature I found on the Web on the subject of torque steer said that it often occurs when suspension is worn, and is often manifested by problems at the wheel diagonally opposite the corner where suspension is bad. I knew by this time that the shock on my right rear corner was a goner, and that the steering jerk problem I was having seemed to be occurring primarily at the left front wheel. But I didn't use the car a lot during the last half of 2004.

Finally, 3 months ago I had the damper parts of the MacPherson struts on this car replaced; a 4-wheel alignment was also done. I had hopes that this would fix my jerky steering problem. It did not; it's as bad as it ever was. This car is also very hard to keep in alignment, too. A shop will align it and in no time flat it is out of alignment and pulling to the left (it's been a pretty chronic problem on this car.) The front tires are wearing very fast.

I had the idea to detach the power steering belt and drive around for a while without power steering. My reasoning was that if the jerky steering did not happen with the power steering out of service, that I could be sure the power steering was causing my problem. I talked it over with a mechanic, and he advised against it. He said it was potentially dangerous to drive this car without power steering. And he also said that there is sometimes wear in the "rack" which can cause a problem like mine. This car has rack and pinion steering, and the rack is moved by the steering wheel, with, of course, power assistance.

I pondered what the mechanic said, and came to discount his theory of rack wear. For one thing, ever since I first noticed the jerky steering in March `04, actual manual steering on this car has worked fine. Whether I am turning the wheels slightly or a lot, it has been very responsive, with no feeling of looseness or wander in steering. So I don't think there is any significant wear or mechanical hangup in either the steering mechanism or the power-assisted rack.

I read recently that most power steering pumps have a built-in recirculation valve that open should pump discharge pressure get too high. And I got to thinking that maybe there's a problem with my power steering pump's recirculation valve. For there definitely seems to be both a bump-up and bump-down in pressure now that wasn't there 14 months ago.

The problem with that argument, though, is that an abrupt change in power steering pump pressure would not necessarily result rack motion, because with the steering mechanism in a neutral position, an increase or decrease in output pressure would be felt simultaneously on opposite ends of the hydraulic cylinder which moves the rack, and cancel out. Or so I think - perhaps incorrectly.

And for what it's worth, I also see a lot of wear on the rubber cushions where the ends of the stabilizer bar join the control arms. The wear is particularly bad on the passenger (right) side. (Per my Haynes manual, these cushions are inserted to adjust caster during alignment.) Evidently the stabilizer bar is taking quite a beating.

Anyway, this problem has been frustrating me for a long time, and I'm putting it out to the newsgroup for input and suggestions. If I was pretty sure that replacing the power steering pump would fix my problem, I'd do it, but I'm not there yet.

Thanks in advance,

Mike

Reply to
M. Hamill
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Mike, you need to understand that older vehicles will get less stable if the front and rear suspension/steering gear is not kept in reasonable condition.

There are *many* points in the suspension/steering which can cause the tracking problems you have and as such a proper inspection will pick-up any bushes/balljoint/tie-rod end/ strut/ strut mount which has increased movement,..especially if only one side is worn more than the other. as this also increases torque-steer on that side.

If your steering rack has lots of play or movement, then this can allow small tracking probs simply because your hands are not holding the car on-line. As to torque steer,..a worn rack would not contribute to that, only reduce the driver's response in correcting any pulling.

The alignment parameters: castor and camber are particularly relevant to TS and tracking problems. If castor is less on one side, then the car will pull to that side on both rear and front WD cars. Too much neg camber on one side will cause pulling to that side. The road wheel's tendency to TS will be worsened by these same parameters being out of tolerance.

Car manufacturers try to cancel the effect of TS by keeping both sides TS equal.

Often when a steering alignment shop has an old car, they will ignore any play or movement in the steerin/suspension and just make adjustments as the car is sitting. The car isn't moving of course, so any wear is not considered.

In the final analysis, a proper inspection is the only answer.

Jason

Reply to
Jason James

I agree with Jason and would suggest you check steering soon just in case a steering component or the rack and pinion assembly is loose which could cause steering failure. One other thing is motor/transmission mounts. If one or more of these are bad the engine/trans can move, causing jerking. HTH, davidj92

Reply to
davidj92

Reply to
M. Hamill

I see your reasoning,...but it's a very long-shot. If your PS was applying more effort (thru its hydraulics) to one side relative to the other,..then you would see this effect demonstrated by raising the front wheels off the ground,..start the engine and slowly move the steering from one lock to the other. If there is an unatural bias,.your wheels should move by themselves to the side which the vehicle is pulling to.

The pressure regulator valve will keep pressures from going too high,..but I suspect its action is subtle, not sudden.

Because the port to the left side of the cylinder is open

The test I mentioned should demonstrate this, if its occuring.

I think you are over analysing your problem. As I said there are many things which will cause wandering or pulling,..everything from tire anomolies to an acumulation of alignment errors and /or wear. The Camry IME is a very stable car, tracking-wise. In light of this your problem should be fairly obvious to the trained steering specialist.

NB

Some causes of steering probs I've experienced:

My old Ford V8 had a front tire which was delaminating on one shoulder so thet the tire had a slightly wider diameter on the outside shoulder to the inside,..this caused dramatic pulling away from that tire's side/

Chrysler has a different brand tire on one rear wheel,..

Too little castor,..one side caused pulling to that side (Chrysler)

Badly worn idler-arm (recirc ball steering) caused toe-problems that side and pulling

High crown roads (not flat) caused pulling to verge. Normally castor is set slightly heavier on the kerb-side to counter this.

Brake drag one side = pulling (VW Passat,..heap of shit car)

Too positive camber caused severe tracking instability (Chrysler had its torsion bars raised on front)

Too wide a tire on rear caused dangerous instability when moderate steering corrections were made (Chrysler again)

Sudden changes in cornering radius caused by badly worn strut top mounts (tire would go positive during cornering,..Passat)

And probably more I cant recall right now//

Jason

Reply to
Jason James

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