Tie rod steering adjustment

Right now you don't know which tie-rod is off-kilter, of if they both are. I think I can say this much though, when you're finished and the car rolls straight, the wheels should be about 1/8 inch pigeon-toed as measured between the inside rims at the 9 o'clock and 3 o'clock positions. In the old days we would use two sticks to measure the toe-in, as in this VW illustration.

 

WHY is it off? There must be a reason for that. Are the tires wearing normally?
It could be electric. Does the car steer okay? Does it go straight on highways, or does it pull?
You could switch the front tires and see if it changes where the steering wheel is.

 

You've got something going on that is outside the range you would adjust by tweaking the tie rods (zero to five degrees at the steering wheel, according to T-ST003-01.pdf, which is a good document to study for the details of doing that).

Honestly, at 15 to 20 degrees off, I would wonder if someone had removed the steering wheel at one point and put it back on misaligned. I would start by removing the wheel and setting it back on the column shaft as close to centered as possible, and only then tweak out any remaining error.

Careful when remounting the steering wheel to the column shaft: they have splines, so as you lower the wheel very gently you will feel there are only certain ways it sits on the shaft. But the splines are very fine and very shallow, so (a) you have a lot of choices for how the wheel goes on, and (b) it would be shockingly easy to grind the tiny splines flat by mistakenly turning the wheel before it's fully settled in and secured. That would be destruction of the wheel and the column shaft.

T-SB-0391-08.pdf is another good document to look at; it steps back and explores a lot of the other reasons the steering could be off.

 

I recommend having a thrust-angle alignment performed. If the steering wheel is suddenly off-center there is a good chance that your vehicle is out of alignment.

15-20 deg is not very much. If you re-positioned the steering wheel by one tooth, the change is usually closer to 45 deg or more. Don't ask me how I know...

 

I'm skeptical. For a one-tooth offset to be 45 degrees, the count of splines in the shaft and steering wheel would have to be 8 (360 ÷ 45). That's not many at all; the wheel and shaft would look like the cylinder head bolts.

I don't have a taken-off Prius steering wheel handy, but I do have a taken-apart Gen 1 steering rack downstairs, and its input shaft where the lower steering column attaches has 36 splines (± a couple if I counted wrong). My recollection of the steering-wheel end of the column is at least that many splines, if not more (that's why they're so shallow that flattening them is a real possibility during wheel reinstallation).

So let's say it's 36 splines. That's just 10 degrees per. With the OP reporting up to 20 degrees offset, the wheel might be installed one or even two splines off.

 

Respects...but since you don't know what you are doing, I would suggest you have this done by an alignment mechanic with the proper equipment. Even if you had an idea and you get it close, you still need to rack it to do finals. This didn't happen by itself and there are other things that need to be looked at...get it checked.

 

I think you should have mentioned that.
So you probably don't have anything damaged, just a bad alignment.
You should take it back and make them do it correctly.

 

Still...not something you want to "learn" to do now, especially under those circumstances. Now is you had just rebuilt your front end, we could get you close enough to get it to the alignment shop.