I installed a used set of springs of an MP3 on my es. Now the car drifts to the right when I let go of the wheel. I took it over to Goodyear to get it aligned after I installed the springs, and the tech said the alignment was dead on. What else could it be? Anyone with ideas, please help.

 

A couple of possibilities spring to mind...

1) Are the tires installed in the same position as before? Steering pull is often caused by the tires, particularly if one side is more worn than the other. If the tires aren't directional, try swapping the fronts side-to-side and see if this changes the pull. If they ARE directional, try rotating the rear tires to the front.

2) What are your actual alignment numbers? Many alignment shops that mostly do day-to-day maintenance work for the average Joe ("I took it over to Goodyear...") will put the car up on the rack, see if it's within factory specs, then OK it and get the car out the door to make way for the next customer. The problem is that an alignment that's within factory specs is often NOT adequate on a car with set-up suspension and low-profile tires. Increasing steering response will also make the car more sensitive to poor wheel alignment. This is especially true because the Mazda specs are too broad IMHO. Post your numbers and let's critique 'em.

Good luck!

 

Thanks for the info, I'll look into the number thing and post them. I'm running stock rims and wheels, I'll try to switch the fronts from left to right and see if that makes a difference.

 

I would take it to a different place to have it aligned. When I had that problem (my car started drifting to the right just like yours immediately after I replaced the front struts a long time ago) I took it to have it aligned and they always said it was dead on. I then tried rotating and balancing as well, That didn't help.

But then I took it to a different place and they had a different alignment system. They told me my right wheel was just a little bit farther behind the left one (but other than that they were perfectly aligned), and the guy asked me if the car drifted to the right BEFORE I could tell him that that was the reason I had brought the car in for service in the first place.

He took this hidraulic piston and placed it inside the wheel well (between the body and part of the suspension right behind where the strut attaches on the bottom (The "Y" looking thing that attaches the wheel to the body... I forget the name), and basically "pushed" the whole thing forward a bit. Problem fixed. Now my car drives perfectly straight.

 

Sounds like your problem is/was caster.
Our cars have a way to adjust caster (and camber a little) by rotating the top of the shock mount (four bolts). On this top (on each side) there is a big white dot in a corner.

First, make sure the dots are symmetrical.

For Less caster make sure the dots are pointing fwd.

For More negative camber, make sure the dots are pointing outward.

I have mine set up with the dots pointing fwd and out and it doesn't want to drift.

I used to have it setup with the dots pointing out and back- with more Caster) and the car would drift to either side (right sometimes, then left sometimes). If your dots are not symmetrical, than your caster is different and it would just pull to one side.

For Autocross racing you would want more caster, as it give a more direct steering feel. However on the highway, you find youself gripping the wheel, and constantly adjusting to keep the car straight.

 

That's very interesting about Caster, never heard of such a thing, I'll look into it, thanks.

 

I suspect that when you re-installled the struts after installing the springs, one of the strut tops did not go in the same position as the other one. Like JAS00x said, the strut top is offset from the 4 bolts that mount it to the chassis. Being "off" changes the alignment from one side to the other, even though both sides might still be within factory specs.

 

I think that's the problem, I looked at lunch, and the right side strut has the dot pointing to the outside of the car whil the left one is pointing streight. Am I correct in assuming I'll have to take the strut out again to realign it?

 

Just unbolt the strut from the chassis (undo the 4 nuts that hold the strut top to the car), lower the assembly, rotate it, and re-insert the 4 bolts through the chassis.

 

Thanks, so the dot should be pointing forward correct?? From the factory.

 

Good question... on mine both dots are pointing forward and out. I can't make them point forward perfectly because they are not painted on in a way that would allow that... they can only points to the corners (out-front, in-front, out-back, in back). Which way "should" they point?

 

They can't point straight forward because the dot is on the corner.
I just meant the moving the dot from pointing either fwd and in or fwd and out- you still have less caster, than if it were pointing back and in or back and out.

To adjust it, just take the 4 bolts off, lower the strut/spring assembly, rotate the top part, and fit the bolts back through the holes.

The Dots should be symmetrical. I'm not sure which is stock, but for everyday driving, I prefer them out and forward. This gives you a little more camber (than in and forward), and less caster (than out and back) so the car is not so "drifty" on the highway.
If you are autocrossing, you may prefer the dot to be out and back for a more direct steering feel.

 

Thanks for your help, I now have both dots pointing forward and out. Drove the car around and it made a huge difference. Thanks for you help again, this is one of the great reasons why we have an awsome forum.