Car stalls at red lights. TCS/DSC lights won't turn off. Help!
 

Hey guys. I'm trying to help out a friend here.

Car is 2004 AT with 24,000 miles. For quite a while, his traction control light kept coming on occasionally. Normally a restart would clear it. Today, he got an FM band frequency expander installed, and after that, his TCS and DSC lights are on all the time. He had tried turning the steering wheel all the way to the left, and all the way to the right. Tried removing the battery terminals. Tried resetting the ECU. He even did the 20 pedal break procedure. Nothing worked.

For quite a while, his power steering has been acting up too. The wheel seems to vibrate, or "shudder" at around 120 degrees. It seems like it's moving on its own at times. But it only moves about an inch. Never more. We have cleaned the Power steering connectors and the torque sensor. No luck. Could this have a connection to the TCS/DSC lights?

However, after resetting the ECU, whenever the car comes to a stop, it stalls. Starts right back up, but whenever he stops at a traffic light, the car stalls. He can start it back up in Park, shift in to Drive, and the car would not stall. But as soon as he starts moving AND THEN come to a stop, the car stalls. AC on or off after restarting the car, it doesn't stall. But he noticed the car seems like it's about to stall when the AC is on. But won't actually stall until he starts moving and comes to a stop.

There was a thread on here way back that I remember reading about a similar issue. It turned out to be a clogged SSV.

Could this be the same? The car does make a ticking sound at idle, and it sounds a lot like the SSV.

Thank you.