Ok, I have an 84 S. I noticed today that just creeping along at an idle while not holding the steering wheel, when I hit the brake she pulled to the right. Then while in reverse at an idle, I hit the brake, the steering wheel spins counter clock wise sending the front end hard right. My guess would be the right front caliper sticking or could there be more to it. Thanks. Mike......

 

What heat difference is there between the front rotors after a run?

Pulling to one side may indicate that one of the calipers/brake is not functioning properly; the left in your case.

 

Thanks Malcom. Not sure of the temp difference between the rotors. I could bring he thermal laser gun from work to check it. You say the left brake? I would have thought the right brake seeing how it pulls to the right whether I'm going forward or reverse.

 

For the car to brake straight each corner has to be working somewhat equally; if the LH front isn't but the RH is then it may be the reason for the pull to the right.

Be very careful; there's obviously an immediate need to rectify this issue.

 

your brake system may be a diagional system meaning that one front and the opposite rear brake are tied together so check all of the wheels with the gun if one front and the opposite rear are warmer than the opposites then you master may be failing internally

 

If there is a serious issue, I would think your hand would tell you which wheel was hotter without needing to know the actual temperature. On mine after a 60mi run in an hour, the wheels are just warm to the touch.
jp 83 Euro S AT 51k

 

I would start by jacking the front of the car. Have an assistant very gently apply the brakes as you spin the front wheels by hand.

If there is no noticeable difference in brake application, try swapping the front wheels temporarily (be sure to swap them back) and see if the problem changes. That will tell you whether it is tires or brakes...

If nothing shows up, repeat the tests on the rear.

 

If you have the car on flat (FLAT!) ground, its very easy to detect a dragging brake - get it rolling a touch, and let it roll to a halt naturally without brakes, sitting in it. If it just stops, brakes are not doing it. If you feel a small lurch, something is dragging. Practice in another car, using a tiny amount of brake, and you will see what I speak of.
jp 83 Euro S AT 51k