Power Steering

[jthailer]

2003 Boxster S 30k miles purchased 1,500 miles ago. Recently the "on center" feel of the steering feels loose or vague. When turning it feels fine. On center it just doesn't feel as tight or responsive as when I purchased the car.

I have checked the power steering fluid when cold and the level was OK. I was thinking of checking the level when hot and/or flushing the entires power steering fluid.

Could this be a steering rack problem? I had a full PPI done before I purchased the car and I believe they checked the steering rack.

I only use the car on nice days and only on weekends. I do drive it pretty hard.

[brucenoah1956]

It is highly unlikely to be the power steering pump. All the pump does is provide power for hydraulic assist. The only way a power steering pump can create a vague on center feel is if it produces too much flow. That can only be caused by a stuck flow control valve in the pump. If that has occured you will note other problems like loss of power assist at idle or when decelerating on an off ramp.

Your problem is likely one of the following,

1. Tires - inflation and tread condition can influence what you feel.

2. Wear in the R&P gear, or worn suspension components or tie rod ends. Check for free play around center with ignition switch in position to unlock the column but with the engine off. If there is play in the steering wheel as you rotate the wheel back and forth holding it with one hand between your thumb and forefinger, you should start inspecting where the plat comes from.

3. If you don't find any problems with the above, is it perhaps just an ubsubstantiated feeling?

BTW, I've been a steering engineer at TRW for >30 years.

[jthailer]

It is highly unlikely to be the power steering pump. All the pump does is provide power for hydraulic assist. The only way a power steering pump can create a vague on center feel is if it produces too much flow. That can only be caused by a stuck flow control valve in the pump. If that has occured you will note other problems like loss of power assist at idle or when decelerating on an off ramp.

Your problem is likely one of the following,

1. Tires - inflation and tread condition can influence what you feel.

2. Wear in the R&P gear, or worn suspension components or tie rod ends. Check for free play around center with ignition switch in position to unlock the column but with the engine off. If there is play in the steering wheel as you rotate the wheel back and forth holding it with one hand between your thumb and forefinger, you should start inspecting where the plat comes from.

3. If you don't find any problems with the above, is it perhaps just an ubsubstantiated feeling?

BTW, I've been a steering engineer at TRW for >30 years.

Thanks for the reply. I will check the above. Could just be my imagination. If this is the biggest problem I encounter with my car I will be very happy.

[seafeye]

It is highly unlikely to be the power steering pump. All the pump does is provide power for hydraulic assist. The only way a power steering pump can create a vague on center feel is if it produces too much flow. That can only be caused by a stuck flow control valve in the pump. If that has occured you will note other problems like loss of power assist at idle or when decelerating on an off ramp.

Your problem is likely one of the following,

1. Tires - inflation and tread condition can influence what you feel.

2. Wear in the R&P gear, or worn suspension components or tie rod ends. Check for free play around center with ignition switch in position to unlock the column but with the engine off. If there is play in the steering wheel as you rotate the wheel back and forth holding it with one hand between your thumb and forefinger, you should start inspecting where the plat comes from.

3. If you don't find any problems with the above, is it perhaps just an ubsubstantiated feeling?

BTW, I've been a steering engineer at TRW for >30 years.

Can you tell me if you can buy the ball joints for the boxster seperately? They are a TRW part no? I have searched hi and low and can't find a thing.

I have a buddy who can make billet control arms but we need the joints...thx

[jthailer]

Steering seems very tight when not moving. I tried the thumb and forefinger technique as you suggested without the engine running and with the engine running. At this point I agree that the feeling has a lot to do with tire pressure and outside tempurature.

Another question: The 30k mile service says to inspect the steering bellows. What exactly are the bellows?

Thanks,

[brucenoah1956]

The steering "bellows" are the polymer boots on either end of the rack and pinion steering gear that cover and protect the inner tie rod ends. Their function is similar to CV boots, with the exception that they only have to flex, not rotate also.

Look for components on the front axle just inboard from the outer tie rod ends that are similar in appearance to the CV joint boots on the rear axle.