Steering coupling play with VIDEO, Help please!

[blefevre]

Okay, so I finally pinpointed where my "dead zone" is coming from. Here is the problem I have been seeing. 1990 325is airbag car.

I have more then normal steering play. Along with the 2 or so inches of play, there is a resistance that once overcome the wheel will rotate another 30 degrees or so before any steering happens. This occurs when turning right, then upon the next left turn. It's unpredictable because it takes a certain resistance then the big rotation occurs. It's pretty dangerous on curvy roads.

Here is a video. I would say that there is some "play" in the guibo. There is a small "clunk" when I push and pull it.

Look at the bottom of the coupling, closest to the rack. Whenever I reach that "deadzone", the coupling moves down, towards the rack, a few millimeters. That is my problem.

Do you think the coupling or the rack is the problem?

http://www.youtube.com/watch?v=HspUnSSr5CE

[george graves]

Awesome work posting a video. But it's hard to say - are the bolts on the spline tight? Either the flex disk is broken(looks that way), or the rack is fubared. I'd R&R the whole kit and kaboodle if it was me.

I know that doesn't help too much....I'm sure others will chime in.

[jlevie]

From the video I'd say that the coupler is okay, but the rack is bad. There should be no in and out motion of the rack input shaft.

[blefevre]

From the video I'd say that the coupler is okay, but the rack is bad. There should be no in and out motion of the rack input shaft.

What is holding the input shaft in place? I can't find a cutout diagram of a rack.

Edit: I did find this.

http://home.comcast.net/~adamsjohn/325ic/work/SteeringRack/steeringRack.htm

[CarsSuck]

yes, picture #9 in that link.

Do you by any chance get odd shimmy in the wheel over rough pavement, or any shimmy at all?

[blefevre]

There is no shimmy or wheel vibration at all. I tried tightening the input shaft bolt (#9 in the link) and it didn't budge. I am going to give it another shot tonight. From the pictures I am seeing on the input shaft I have absolutely no idea how the input shaft can be moving up/down if that bolt is tight. Ugh.

[blefevre]

I tightened the coupling a little (wasn't loose). I also tightened the pinion shaft lower bolt. However, I had to use my breaker bar and a ton of force. I got it to budge but stopped pretty quickly because I was putting so much torque on it. It didn't change anything.

I guess I can only go with "rack is bad". Which sucks because I wish I could figure out WHY the rack is bad instead of just guessing.