Steering problems, need advice..

[Bumble-Bear]

Hey Jefferios,
I did have the smart service advisor ride with me. He felt the same feeling of the car pulling one way then pulling the other. It was submitted to smart headquarters for their advice on what the problem is and how to fix it, but there has been no word back. On the day the advisor took it out with me, we had some strong and steady winds. Even with the wind blowing from one side of the car, it would pull away from the wind and a moment later it would be pulling into the wind. The advisor and I both thought that with steady wind, it would pull away from the wind at all times. Oh well, we will see what the front end place finds.
Ryan

[John_H]

If the wind were steady you'd be correct. But if it's running from 30 to 50 mph, it's the same as a 10mph wind coming at you one way then the 180º other from the perspective of holding the car steady.

[jimvw57]

When my Smart acted like that, I found the tire pressure was on the high side. I lowered it to the pressure posted on the door frame and it got much better.

I have had bad experiences with certain brands of tires giving a squirrely feeling. I switched my truck over to Michlens and it is like a whole different truck now.

Again, assuming tire pressure and alignment is correct, and no damaged rims etc.

[fortow]

The dealership may not be doing a careful job of checking and adjusting alignment. You may have toe-out instead of some toe-in.

You can verify this yourself to see if it's in the ball park. On a level surface drive straight ahead and stop. Measure from one rib in the tread of the tire both on the forward and rearward sides carefully with the help of an assistant. Do the measurement as close to the hubline as possible. Your measurement should be either exactly the same or slightly wider at the rear of the front tires. The difference will be in millimeters so measure carefully. If you find a wider measurement at the front of the tires then that is your problem. Another indication of incorrect alignment would be tire wear. If the inside edges are a little more worn than the outside edges of the tread that would also indicate toe-out. Some toe-out is reserved for circuit racing only where turning is the priority. For street cars straight line stability is the priority and toe-in helps that. The car should have no toe-out!
You might also want to have suspension linkages checked.

Incorrect positive caster could also be part of the problem.

[SMARTPLUG]

I will throw my 2cents in. The problem you describe sounds like one fo two things. The toe set to toe out or something wrong with the steering position sensor in the steering rack. I noticed a wander in my 09 passion so I put it on the alignment rack at work and checked it like I do with all my cars when I first get them and it was toe out instead of toe in. I drove home on the expressway it was better but I like a car to hold better than that so I put 16" tires and wheels and WHAT A DIFFERANCE! Drives great. I new from my 30+years in the auto industry the a tiny car like the smart was not going to hold the road lik a Mustang GT but I knew I could do a few things to make the car handle like a go-cart. The wider tires helped a ton . Maybe a bigger sway bar and stiffer springs? One more thing the dealer might try is to disconnect the wires to the power steering rack and drive it to see if that makes a differance. It won't take but a few minutes to try and would rule out the rack as the problem. Sometimes you have to think outside the box on mystery problems hope that helps . Bob.

[sato7]

Bumble bear I had the same issues since the car was new, I also had a hell of a time with the smart center service. I ended up putting OEM rears up front and that helped allot. the car still feels like the power steering is fighting you and I think it is... I've read that the electric power steering in our cars has a self centering mode that learns AND readjusts its CENTER. Now with that info and the kind or rear suspension the smart has.... I think it's called a Celion suspension, basically its a large C pivoted in the middle. that makes it really susceptible to bump steer. Bump steer I think is when you hit a nuance or bump in the road with the rear suspension or when the rear is loaded by cross winds, that affects the front suspension and steering. By reverse engineering why the Brabus has stiffer springs up front, stiffer torsion bars and the front air dam, I'm thinking they tried to tackle this issue.

[Jim R]

I agree with Smartplug about disconnecting the electric power steering for a test.It makes a lot of sense.

[jefferios]

I think it does try to recenter, when I was driving a Brabus on the highway I felt this force on a long turn to recenter the car.