97 GC Front Brakes lock up when started

[pmartinez06]

Hello all. I have a 97 GC 3.8L with an unusual brake problem. New pads and rotors but, when the vehicle is started the front brakes immediately tighten. I can put it into D and R but no go. I can feel the tranny engage but no go without SOME gas. If I leave it in N and shut down engine, I feel the brakes release and it'll move. Upon restarting, brake pedal sinks slightly and front brakes are tight. Visually all is ok. Brake pads and rotors done 6+ months earlier and working fine until lately. Fluid level is OK. It's stuck at my buddy's house. So, I haven't been able to do much inspecting or troubleshooting. I searched through 137 pages of the Dodge Caravan threads without any similarities. Someone have any suggestion?

[corning_d3]

Is there possibly a broken return spring on the pedal, or a misadjusted brake pushrod?

[dbfordtech]

With the engine off, unplug the vacuum line from the brake booster, and plug the open end of the hose with something. Then start the engine and see if you can
drive. But beware, if this works you will not have any power assist on your
brakes. You will have to push the pedal very hard to stop.
If your brakes are now released when the engine is running, go out and get a new brake booster.

[slantsixness]

Look under the van (while running, and CAREFULLY with a helper!) and see if your ABS pump is running wild, or one of the brake lines is rusted out to it.

Also, if your van has it, turn off the traction control, does it still do this then?

A bound up brake pedal (like a wire caught in the pedal shaft might cause this, and so could a vacuum leak at the brake booster.

Are you sure the brakes are applying, or is the Transmission locking up (feels the same)?

If you pull back on the brake pedal, does it release?