1994 850 Sedan Odd intermittent bad wobble problem

[dconklin]

This is going to sound crazy to some, but I am starting to think that this might be something electrical causing this but no idea for sure. Hoping somebody may have an idea!

Ok here it goes:

We bought the '94 850 sedan a couple months ago. I can tell by how low it sits that I will be needing to replace the shocks in the back and struts in the front, but we are pretty much ready to rule these out as our current wobble problem. This is a little complicated so I am going to do my best to explain.

The car has a kill switch on the front under the bumper. We are the third owner and the lady we bought it from said she thinks the first owner put it on due to a drain on the battery. So in the beginning we pulled the kill switch key out each night. But then we started to have problems starting it. You had to wiggle the key a bit to get it to give a good connection on the wire that connects the battery back onto the rest of the car. So we decided to just keep the key in it to see if we would have a dead battery. Nope we have let it go a few days and starts, tho once in a while the killswitch key needs to be pushed on to make a good contact again. So I am sure that driving it may occasionally disconnect the battery in the middle of driving. Blinkers always light but intermittently the flasher doesn't work and we have to manually flash the lights (I have two theories on that one and not my biggest worry just throwing it out there in case by some chance it is related to the rest of our issue.)

My biggest worry is this awful wobble we get in the front of the car. It started happening more often at low speeds (around 25 mph.) It really started not long ago (and yes we have been keeping the kill switch key in now) and it scared the crap out of me. It seriously felt like the wheel was so loose that it was going to fall off while driving. Now I knew the front tires were in rough shape, but was going to wait until the struts were done originally. But after that wobble, we went that day to get 2 new tires put on the front. Drove nice for a little while and then the wobble was there again intermittently.

You can take your hands off the wheel when it acts up (doesn't wobble all the time) and it stays perfectly straight. You don't feel the wobble in the steering wheel either. But you can feel it sitting in the car as it seriously feels like the wheel is going to fall off (the best way I can describe the wobble.) Doesn't matter if you are braking or driving, engine doesn't seem to hesitate either. But the one thing I noticed the last couple days is that when it does act up, if you turn the engine off it is ok for a little while upon restarting. The car can be off for just a minute and when you restart, the wobble is gone. When the wobble is acting up again, it can be at an idle too not just while driving.

This is driving us crazy! Anybody have any ideas as to what can cause this wobble that happens intermittently?

[jreed]

To be safe, if you haven't done it already, I would recommend a thorough inspection of all the suspension and steering related components including the ball joints, tie rod ends, bearings, etc. It sounds like you may have a component that is loose, broken or about to fail.

[Ben850]

To be safe, if you haven't done it already, I would recommend a thorough inspection of all the suspension and steering related components including the ball joints, tie rod ends, bearings, etc. It sounds like you may have a component that is loose, broken or about to fail.

I agree with everything said here. If the car is visibly not sitting correctly, it would indicate a suspension anomaly. Possibly delta arm bushings/links in the rear, or control arm bushings or strut seats in the front.
I have a shudder going on in my sedan after enduring the potholes here in Michigan over the winter. It is a '93, and I am sure all the rear delta arm parts are original. I've been putting it off, but plan on taking care of it this summer.
Keep your hands on the wheel for the time being until you figure it out.

I realize you said front wobble. Usually tie rod ends, or lower ball joint. I did replace everything up front, including those.

[dconklin]

To be safe, if you haven't done it already, I would recommend a thorough inspection of all the suspension and steering related components including the ball joints, tie rod ends, bearings, etc. It sounds like you may have a component that is loose, broken or about to fail.

I definitely want to have my Dad look over all the suspension parts and I am quite sure it does need struts. I was hoping it would make the distance tho because he is 3 hours away and there is no way he can work on it at my house. Tho he hasn't worked on many Volvos (except the 82 I used to have), he has been a mechanic for many years. Just don't know if I could make it out to him. I have on street parking on a very busy street in town

The check engine light is on and is there anything with this that could cause it to wobble? It seems to act up more at a lower rpm then when on the highway. The 2 times it acted up on the highway, it only did it for about a minute and then stopped and went back to driving good again. I didn't lose speed but on the highway it was almost like the car didn't want to give the extra effort to go up the hill I was on so it stayed at around 60 MPH until the wobble stopped, it then went back to driving ok. At low speeds it won't stop wobbling until you turn the car off and restart it. Then the wobble is gone for a little while

I would hope that STS would have said something if there was anything they noticed wrong when they put the new tires on the front a little over a week ago, but not sure they would have done so without me paying for an inspection.

Went to Autozone to have them hook up the computer but they can only go back to '96 and I have a '94. They told me a '94 needs OBD-I but I read I should have OBD-II. I checked for my OBD-II and it has "OBD-II" on my coin holder with a spot for the connector, but no connector there. There were 2 connectors under the ash tray, but they were both plugged into something going back into the dashboard. Think I will have to manually check the codes which is something that I have never done.

[dconklin]

Our broken motor mount bushing

broken motor mount.jpg (88.91 KiB) Viewed 606 times

I hope the picture comes up ok, this is the first time I have added one. I found the problem, at least probably the biggest part of the problem! The motor mount bushing is completely shot. I only quickly looked at the motor mount arm before and didn't fully inspect it before. Motor mounts are something that I didn't know exactly what it was supposed to look like. But upon closer inspection I noticed that there was pretty much no rubber there holding it in place. Now to find the part because the local part stores don't have it listed, they have a different part which I am assuming are the bottom mounts (for over $100 each too!)

But at least I know what our problem is now

[mikealder]

The easy option is to replace the upper arm bush with a poly-bush such as this one http://www.ipdusa.com/products/4738/111 ... izer-mount I would also take a good look at the lower gearbox torque link bushes as these get hammered when the top mount dies, the lower gearbox torque mount goes between the gearbox and the front portion of the subframe it looks like this http://www.ipdusa.com/products/5824/112 ... rque-mount

You will experience slightly more vibration through the bulkhead with a top mount changed to a poly style one but they are much easier to fit, if you don't want the poly type you can get a standard one such as this http://www.ipdusa.com/products/9896/121 ... gine-mount but these are a little more "fun" to fit - Mike