Car Analogy

Recently had an alignment, and now car handles much worse.

Owned the S for 1 year. '06 with ~86K miles on it now. Best handling car I ever owned. Very capable, very stable, glued to road, confidence inspiring. Its my DD, and I drive it year round, except when there is actual snow or ice on road. Its 100% stock. Stock height, stock struts & springs, stock wheels, stock tire sizes.

Recently got hit in rear. After the accident the car was drivable, so I drove the it home about 30 miles, and of course was paranoid about frame/suspension damage so was alert for any anomaly in how it drove and handled. To my relief it was all the same as pre-accident.

The body shop replaced the left rear Q-Panel, and the rear panel that the tail lights mount to, as well as some trunk floor metal straightening. They found no frame or suspension damage (and based on hit I can’t see how there could have been any).

As part of the repairs they also sent the car out for an alignment at a local, reputable shop. When I got the car back, I drove it to work and immediately noticed a handling difference, even though I was taking it easy. It just didn't feel as planted. Changing lanes on the highway I could feel the back-end wander over imperfections in the road. Accelerating briskly from a stop, when I’d let off and push in the clutch, the car felt squirmy. It just didn’t feel right, it felt like the rear tires were very low on air. So on the way home I checked the air pressure. 26 psi in all 4. Not pleased they didn’t top them up to recommended 32 psi for the alignment, but at least they were all the same. I set them all to 32 psi to see if that made any difference. It didn’t.

Since then I also drove the car a little harder, and it doesn’t feel like the same car as pre-alignment. Its not as planted, does not inspire confidence. It feels ‘loose’ around corners, and the back-end now slides out under power all too easily. I thought they must have messed up the alignment settings. I especially wanted to see if they set the rear toe wrong.

So I got the printout from the alignment, which is above. I can see they set things to the correct specs. The front Caster is off spec, and its not equal side-to-side, but those settings they didn’t change. They are the same as before. So while I’d like to see them fix that, especially so its equal one side to the other, the Caster doesn’t seem like it’s the culprit. The other settings all seem to spec.

They did make large changes to the rear toe, much less toe in than before, but it was out of spec before, and now its spot on to US Honda specs for AP2.

I don’t think the problem is due to the accident, for 2 reasons:

- It drove fine after the accident on way home, and later on way to body shop (40 miles total)
- If the accident bent something, frame, suspension, etc, it would have shown up in alignment (they wouldn’t have been able to get it in spec or initial readings would have shown something way off on one side, etc)

Full disclosure, my rear tires are getting close to replacement. The wear bars are getting close in the center section of tire. Sides have a bit more meat. But the tires were the same before the accident, so I can’t see how they are the issue. They are Summer Max Performance tires, Kumho Ecsta LE Sport. Stock wheels and stock tire sizes.

What can be pinpointed as changed since car handled great, till car handles poorly? The alignment.

Anyone have any thoughts on why my car doesn’t feel right anymore?

- Did I get spoiled by the excessive rear toe I had prior to alignment? (maybe the way my car handles now is the way its supposed to? God I hope not)
- Maybe the excessive rear toe was covering up for the worn rear tires, and replacing them (which I need to do soon anyway) will resolve things?
- Maybe the excessive rear toe (or one of the other changes they made to bring it to spec) was covering up for the messed up Caster? (and setting caster to spec will resolve things)?
- Maybe the specs listed below are not correct? (Look correct to me for AP2 based on compare to stock settings I found online)

This is really affecting my enjoyment of the car. Really hoping someone has some answers. Any suggestions appreciated.

aeonracer

More rear toe in stabilizes the rear under power delivery / drive out of the corners, as well as high speed straight line stability. If you had a lot of rear toe in before, and now are back to stock-ish numbers, that's probably where your "issue" is. The other is a flat out wrong alignment, which I've had happen before (i.e. their print out wasn't even close the actual numbers, and my car felt horrendous until I went to a reputable shop and got a proper alignment).

The stock alignment isn't terrible, but I personally like a little more toe in, ~ 0.25". Stock AP2 is ~ 0.15" total.

iamxpl

go to another shop and get a different set of hands on the alignment. a good shop will have a hunter machine. also, when you got in the accident did they check your rear subframe alignment?

Car Analogy

Good question about the subframe alignment. I do not know if they checked that. I will look at it next time I have car on jacks (I'll just stick a tool into both alignment holes and make sure subframe is centered).

But if subframe was out of alignment, wouldn't the wheel alignment be difficult to adjust to spec and have been way off for initial pre-alignment readings?

iamxpl

it could still be in spec. now im not expert, but the alignment machine only calibrates the suspension setting. if all the settings in the rear was correct the machine wouldnt know the difference if the subframe was moved as a whole. its been well documented that a subframe bolts come loose, not on all but a good number has been reported. add that to a collision then it could have possibly moved.

Car Analogy

If the subframe moved perfectly sideways, or perfectly forwards or backwards, maybe I could see alignment measurements not showing the misalign, but in all probability subframe would move crooked.

I can't see how that wouldn't show up in the alignment.

iamxpl

most machines use a on wheel device. which will only calibrate the alignment settings. it will not be able to tell if your subframe has moved. all those suspension components attach to the subframe. think of it this way. take a perfectly good aligned car. loosen the subframe and just move the subframe only. check the alignment again. nothing would have changed. the machine will not pick up the movement of the subframe. or i can be wrong lol

AP1Driver

You're correct. Subframe shift, even severe, would not change the alignment specs other than if you are looking at wheel to body measurements, which would be off side to side and/or front to back..

Car Analogy

I was under the impression that some of the alignment settings were referenced back to front. Is that not correct?

iamxpl

front and back alignment have no correlation to each other when one is changed.