No return to center in steering

Steering gears don't really have "center points" to set in that sense. I mean, obviously, there's a point equidistant from both ends of the rack, and you kind of want that to be when the car goes straight (tie rod adjustments dial that in).

But it's not as if there's any kind of spring in there trying to return things to a "center" point, and it's not as if the electric steering assist tries to return it back there for you. The return to center force just comes from the weight of the car and road forces acting on the alignment of the front wheels.

There is a steering angle sensor behind the steering wheel, which the skid ECU can use to notice when you're skidding (if the steering angle doesn't agree with the way the car is going). It calibrates itself on each drive (when you're driving normally and going straight, the ECU looks at whatever number is coming from the angle sensor and says "we'll call that zero").

In cars with parking assist, the angle sensor can also be used for that, and the parking ECU does have a "reset zero" function. If it is off, the parking assist and the guidelines shown in the backup camera may be off.

 

I don't think that's the case. While there is a steering angle sensor (it lives right where the spiral cable is), the ECUs in the car that care about it are the skid ECU and (if you have it) the parking assist ECU.

Surprising as it may seem, the power steering ECU doesn't give a hoot about the steering wheel angle sensor. That isn't even an item in the power steering data list.

The steering ECU gets all it needs from the steering column torque sensor (which lives right near the electric assist motor). That only measures how hard you are turning the wheel, not which way the wheel is pointing. When it senses you giving torque to the left, the ECU gives more torque to the left. When you give torque to the right, it gives more torque to the right. When you're not giving torque, it doesn't either.

The steering ECU also gets the vehicle speed signal; it dials back the amount of assist it gives you, as the car goes faster.

There is a procedure for setting the zero point of the torque sensor. And if that is off, then yes, you'll have unbalanced assist to the left and the right.

There are a couple places in problem-symptoms tables where the repair manual says "steering center point (zero point)" as a possible suspect for "steering effort differs between right and left", but that confusion might have crept in during translation. It's talking about the torque sensor. The reading should be zero whenever the torque is zero, and the torque is zero any time the wheel isn't turning, whether centered or not, as long as the reason it's not turning isn't because you're holding it there.

In the torque zero point setting procedure, they have you point the wheel straight ahead and keep your hands off it, because straight ahead is an easy standard situation. But you could still learn the zero torque value with the wheel pointed another way, as long as there was no torque on it.

 

I believe that it is the camber of the front wheels that provides the "return to center" torque for the steering.

JeffD

 

The steering torque is zero whenever the steering wheel isn't turning, as long as the reason it isn't turning does not involve being held in position.

 

So, did the alignment shop mention anything about the tie-rods being at the max point, so no further adjustment can be made? If not, it sounds like maybe something is bent up elsewhere and some dimension is out of the spec.

 

"My steering wheel isn't exactly centered when the car is going straight" and "after turning, the steering doesn't tend to return by itself toward going straight" are different issues. The first one can be amenable to tie-rod adjustments.

 

Has anyone had any success on this? my daughter ran her 2007 offroad over a curb - I'm having the same issues as above:
- we've replaced tie rods, sway bar connector, control arm, strut, and wheel.
- we've got it aligned as well as the shop was able
- no codes/DTCs
- power steering seems to fight with me if the car is moving, if I turn the wheel at any speed, it wants to stay turned without veering back to center if I let up. it's like the power steering or something binding is holding it off center. Also trying to coast straight ahead requires a sort of slight yank of the the steering wheel back and forth to keep it aimed straight

 

When you say the alignment was put as close as spec how far out of spec is close to spec You got a piece of paper that has green and red crap on it You need to post it up here if you can figure out how to do that take a picture of it with your phone etc The red marks on the alignment paper are the outer spec marks and it'll tell you how far out of specs in the red box If there's a lot of red boxes for either side of the suspension that's not a good thing so it's not very close I'd like to see that alignment ending paper that should be in your glove box when you left the alignment place If you don't have it no well oh well a lot of times the kids throw it out. So that might be a problem I'm having the same problem on an '07 that's not been wrecked or anything it's somewhat returns to center but it has a big clunk in it and it's like something's holding the steering wheel kind of in the straight ahead position when I try to make an adjustment and I've traced it down to the electric steering assist motor right above my knees when I'm sitting in the car I have two of them out they're two different brands for the '04 and 07 up . But they both look the same and have the same connectors just two different names manufacturers so they should interchange I just haven't had time to change it yet in the car I'm talking about I hope I'll get to it in the next few weeks sounds like you may be having the same problem You're alignment people would have been able to tell you that there's no binding or any funny business in the mechanical part of your steering from the rack to the tie rod ends that actually move the hubs and your problem is above that The only thing above that is your steering wheel the assist motor and a yoke and all of that is visible in the car very quickly with some plastic covers off so probably be thinking about rounding up an electronic assist assembly from the same model I would imagine at some place like LKQ you could get that for 50 bucks they might not even know what it is when you bring it up to the counter they don't really care about a lot of this stuff especially at this age I put a picture up of it but that's a real pain here and you can see it on Google all over the place It's just this gold colored silver colored looks like a miniature rack with an electric motor hanging off the side and spline shafts at the top and bottom that's the way I can describe it It has a few gears in it and what have you and I think it's possible for that thing to get messed up whether it's in a wreck or something tweaks it I'm not sure when I get my old one out I'll pull it apart and have a look at it.

 

If you can forgive a small tangential story, it might be useful in this context:
I bought a used car back in the 80s. I didn't know it had been in an accident until my steering arm fell off the frame and locked my wheel in a gradual left turn. This happened on a freeway, at speed, so it was lucky I got it stopped before it had wandered into the opposing lane.

What had happened when they straightened the frame, was that the arc of the steering arm didn't quite match up to the angle of how it was bolted to the frame. After a time, the constant flexing of the metal caused the bolts to break out of the frame. I managed to fix it by making some heavy, over-sized washers for the bolts, and left them slightly loose, so they could slip a tiny bit when needed. The car ran for 150,000 miles after that with no problems.