I have a 90 hatch that runs great but likes to wander a bit on the highway. It's not bad but I was wondering if anyone had any suggestions or if this is just normal for the fox body stangs.
There could be a few issues causing this. Some more probable than others, but I will list them all so you can give them a look-see.
1. Front suspension is out of alignment or damaged/bent/worn.
2. Steering rag joint is failing (likely. mine crapped out and my car started to wander)
3. Power steering rack is dying.
4. Tie rods are worn.
5. Power steering pump is giving uneven boost because of excessive wear.
6. Unibody frame is bent.
A wandering Mustang/Capri is not normal. When my Capri started to wander, I started looking right away and found a large crack in the rag joint (on the steering shaft just above where it attaches to the steering rack).
You'll just have to get the wheels up in the air and start checking stuff. Wiggle the wheel back and forth and look for what's moving. Everything should be nice and tight. The most common causes are the rag joint and tie rod ends.