Diagnosis help...steering odd
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From: Manhattan
Diagnosis help...steering odd
993 cab, Pss9, adjustable sways.
Was on the track a few weeks ago. Car felt a bit unstable at high speeds. Well, not unstable per se, but sort of like you are driving on a bridge and there are gusts of wind randomly...sort of like it was loose in the steering, or something mismatched...was sort of like it would slightly drift or feel slight movement in the steering wheel. Happened straights, some corners, sometimes while braking. Not confidence inspiring.
I had just replaced the rear tires only due to a puncture (perhaps a mistake), so I thought perhaps the differential between not so much traction in new rears (RA/1) due to tall tread (didn't shave) vs. nicely worn in fronts. Played with the pressures a bit, etc. Also noticed that one of the rear shocks wasn't adjusting properly (Pss9).
BUT, when I switched to street tires, same problem, mostly above 80 mph, but some slower as well.
So, had the shock replaced. No luck. Had it realigned. Seemed to help a little, but still didn't solve it.
Thoughts?
I've recently replaced the front A-arm bushings (C Walrod specials). Tires seem good, two sets of wheels/tires in this equation, so doubtful it is a set of tires.
Was on the track a few weeks ago. Car felt a bit unstable at high speeds. Well, not unstable per se, but sort of like you are driving on a bridge and there are gusts of wind randomly...sort of like it was loose in the steering, or something mismatched...was sort of like it would slightly drift or feel slight movement in the steering wheel. Happened straights, some corners, sometimes while braking. Not confidence inspiring.
I had just replaced the rear tires only due to a puncture (perhaps a mistake), so I thought perhaps the differential between not so much traction in new rears (RA/1) due to tall tread (didn't shave) vs. nicely worn in fronts. Played with the pressures a bit, etc. Also noticed that one of the rear shocks wasn't adjusting properly (Pss9).
BUT, when I switched to street tires, same problem, mostly above 80 mph, but some slower as well.
So, had the shock replaced. No luck. Had it realigned. Seemed to help a little, but still didn't solve it.
Thoughts?
I've recently replaced the front A-arm bushings (C Walrod specials). Tires seem good, two sets of wheels/tires in this equation, so doubtful it is a set of tires.
Last edited by JPS; Jul 19, 2010 at 09:50 PM.
Race Car
Joined: Sep 2004
Posts: 4,883
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From: Wilmington NC
check the lower control arm joint nut. Should be a nylon locking aircraft style nut, and if it is loose the joint's stud moves in the bearing housing and is changing your alignment setting on the fly.....ask me how I know 
and then be careful, it could break while at the track! Again ask me how I know this.
Or it could be to much camber and your tires are following ruts in the road (I get that a lot)
and then be careful, it could break while at the track! Again ask me how I know this.Or it could be to much camber and your tires are following ruts in the road (I get that a lot)
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From: Manhattan
I've replace the A arm bushings ala Chris Walrod. I suppose steering rod or something similar? Would the power steering pump or rack/pinion mechanism potentially be the culprit?
Seems that it just doesn't take a nice set...seems the steering wheel, at higher speeds (80+) never really feels planted. Also some bumps seems like I get a higher feedback in the steering than I would expect.
Back at the wrench for the 3rd time today, track event this weekend, fingers crossed.
Seems that it just doesn't take a nice set...seems the steering wheel, at higher speeds (80+) never really feels planted. Also some bumps seems like I get a higher feedback in the steering than I would expect.
Back at the wrench for the 3rd time today, track event this weekend, fingers crossed.
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From: Los Altos, CA
Have you checked your steering links? Do you have the non RS links?
When I pinned my steering tie rod ends, I noticed that the outer portion had moved relative to the inner. The rubber bushing between the inner and outer was more exposed.
So, before I pinned it, I pushed it back into place. I was shocked actually that it had moved. Now that they are pinned, the steering feedback is MUCH more direct.
There is a link somewhere on this forum on the process, but basically, it is 1/4" roll pin which connects the inner and outer halves.
Anyway, something to check that is certainly related to the steering feel.
Pete
When I pinned my steering tie rod ends, I noticed that the outer portion had moved relative to the inner. The rubber bushing between the inner and outer was more exposed.
So, before I pinned it, I pushed it back into place. I was shocked actually that it had moved. Now that they are pinned, the steering feedback is MUCH more direct.
There is a link somewhere on this forum on the process, but basically, it is 1/4" roll pin which connects the inner and outer halves.
Anyway, something to check that is certainly related to the steering feel.
Pete
Burning Brakes
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From: Norway/Iceland
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Joined: Dec 2007
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From: was: CA, 956XX
I bet on tie rod links or ball joints. One or more have some serious play. Could be the rear too. Have all rods checked. This can be done in a shop that has a lift with pneumatic tire trays that sway very fast with short stroke, left and right (90deg.) to the driving direction. You'll recognize any play immediately. Worst case is that a ball joint would snap out of the pan.
Drive carefully and good luck with finding the problem.
Ed
Drive carefully and good luck with finding the problem.
Ed