I have already asked this question on the other TGP board, but it is down and the post is deleted, so here it goes. My brake pedal does not come back up all the way after pressing it in. It stops coming back up about and inch or so lower than it should. This cause the brake lights to stay on. Now some people said I need a new PMIII. My question is, is this a definite thing (PMIII being bad), cause there is no abs light or any other warning light on in the car. In my parts TGP, the relay is bad, and this causes the anti-lock warning light to come on. Should I just replave the PMIII, or should I have the car looked at by me mechanic?
Try adjusting the brake switch. On my tgp, the brake pedal can be lifted past where normal return-to point is, and if that is done, it causes the brake switch to readjust and then the brake lights will remain on. Follow the adjustment procedure (it used to be posted on turbograndprix.com, but the link is dead now) for the brake switch, basically push the pedal down, and release the little metal hook/clip on the switch to allow it to release and then release the pedal, do not pull up, let it come up naturally.
This will set the swtich to top of travel, and if the master cylinder is not binding, all should be good. If the master cylinder is binding, then a PMIII is in order (lest you try to rebuild it yourself, not advised)
Thanks for the help, but I really think the PMIII is bad. But I will try what you suggested. ANd I have one question, what do you mean by "binding"?
I've seen master cyl's that corrode when moisture gets into the brake fluid, and eventually causes the pistons to bind on release, since there is very little spring pressure internally and rely somewhat on back pressure and the little internal spring to evac the cylinder. therefore, if that + the return spring on the pedal don't overcome the resistance of the piston on the cylinder, it won't come back to pedal up position, but the tgp seems to have enough play at the top of the stroke (at least mine does) that the pedal can be pulled up past end of travel, and the actuator rod can actually be pulled partially out of the snap on the PMIII piston, and therefore the brake switch readjusts incorrectly.
Mine was a basket case when I got it, someone did not know how to adjust the switch, so they put a really stiff spring on the outside of the pedal to the bottom of the dash to pull the pedal up, boy talk about a stiff brake, well to fix, remove spring, adjust switch, all is fine.
Try and see, let us know. Good luck.