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Discussion Starter #1
This weekend I drove about 900 miles on the interstate. All was great until coming home today, the last 200 miles or so. I was driving just under 80mph on almost new concrete highway almost the whole way---beautiful highway. Every time I had a gentle right turn in the road, the steering wheel gave a sudden jerk to the right during the turn. It didn't feel like it was binding, it didn't feel like my SS grabbing ruts with those 255/50-17" T/A's and it didn't feel like loose front end parts. If any of you have a full size Chevy 1/2 ton in the mid to late 90's that has the problem with the steering wheel sensor, THAT is exactly how it feels. All looks fine, water pump is dry (not leaking on the belt) so I am stumped so far.

Any ideas???

Carl
 
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Discussion Starter #2
1. check intermediate shaft condition at base of steering column--forward of firewall. This part has a flex joint covered by a rubber boot.
--is boot intact?
--can you move the joint (is it sloppy?)

2. does car have NV7 variable assist steering?
--may be flow control valve is faulty and causing intermittent drop in assist, but that is not liekly to occur in only one direction
--steering gear may be damaged internally, or have faulty spool valve that results in intermittent assist when moving wheel to right

3. if car has steering damper, try disconnecting/removing and see if problem persists
 
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Discussion Starter #3
Bill

I have variable steering. I meant to mention that and forgot. I was wondering if that could be it.

I'll check the intermediate shaft. It just doesn't feel like mechanical binding though, but I'm old enough that I have learned to never-say-never!

The damper is also a good suggestion.

It seemed to me I read of this problem on the forum once before, but I couldn't find it now if there was a topic like this.

Thanks for the ideas.

Carl
 
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Discussion Starter #4
With car on ground, wheels loaded, does the condition exist at all with car not moving?

Suggest you get an assistant and go under car to watch the steering gear sector shaft/pitman arm to see if there is any "unusual" motion when the steering wheel is moved side to side.

Could be interesting....
 
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Discussion Starter #5
Doesn't happen parked. It was happening on every gentle right turn on the interstate. It sure was a funny feeling. It got to where I knew what steering wheel position I could go to without it happening. If I held at just the right spot on a gentle turn and waited, after a few seconds it would give that jerk and we would be turning harder right without me ever changing the load on the wheel. It's just not at all the same feeling as the SS when the 17" Goodrich's grab a groove in the road. This is a sharp jerk just like someone grabbed the steering wheel and gave it a tug. I hope to lift it up here at work and look at it sometime this week.

The only front end part I have ever put on it is a AC Delco idler arm about 15,000 miles ago. The car has about 100,000 miles.

I was wondering if I have a problem with a lower ball joint binding maybe???

Carl
 
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Discussion Starter #6
I'm starting to think there may be a bit of a dead spot on the wheel position sensor that is part of the NV7 system. It's basically a rheostat, but I have no idea what values you would be looking for or what really happens when the signal value "hiccups" over the bad spot. Time to dig into the FSM if that happens to be part of the problem. You could probably disconnect the flow control valve solenoid (at the pump or wherever it's easiest to disable) to see if the problem/symptom changes in any way.

Nothing to tell me the ball joint(s) could be a problem. There are simple checks for that--and if there is any problem with alignment, or keeping alignment, it COULD be a lower BJ issue of some sort, but your description tells me its more noticeable as a power steering system problem.
 
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Discussion Starter #7
Reviving my old post......

This car has been parked for a good part of the past year. We just started driving it again a couple of weeks ago. One of its first outings was another 900 mile interstate jaunt, and same old thing. The right gentle curves are the trigger for it to jerk. I am convinced it's the steering wheel sensor. Has anyone changed one of these?

Carl
 
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Discussion Starter #8
To test, simply unplug the sensor. It should "default" to a static amount of assist.

If the problem goes away, the sensor is toast.
 
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Discussion Starter #9
Thanks, I wasn't aware of that. I'll try it.

Carl
 
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Discussion Starter #10
Does anyone know where the sensor is on the car b/c just today my 95 Fleetwood started doing the samething.
 
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Discussion Starter #11
A couple threads on this in Fleetwood. It's a common hairraiser. The variable assist boost has a bad habit of having a heart attack and overcompensating on gentle sweeps. The only fix is either unplug the ignernt thing near the firewall under the steering column which puts the whole system in "fulltime full assist" with no more variable mickeymouse, or, get some sort of 12.?:1 steering box out of a F- or B- something in a junkyard to replace the 15.?:1 that's stock in the FWD that gives quicker steering and you also don't plug in to anything.
 
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