Ok my name is lucus....got a couple question on the grand prix mclaren....my is the 1990 grand prix with the black and tan interior....ive been told its really rare....ok my problems with the braking system......the brake pedal has no pressure what so ever until i get closer to the floor....when i get close to the full i have pressure and it kinda losses pressure but not really......and it wont kick back up to shut the brake lights off i have to lift it myself everything that ive done doesnt seem to work....ive bled them millions of times....but this is my problem i only have one brake and that is the front driver side....its very strong.....but none other grab execpt everytime i bleed them i can get the driver side rear to grab right after i bleed them....ok well it lasts mabye a day if im lucky...but after that its just that one break....and this is what i dont get i get fluid to every tire has a strong nice stream expect the passger rear...it is isnt like the others its a nice stream but not a strong one....ok....last summer some dum fuck pulled out in front of me and i ran into him....i was only doing about 25 to 20....no severe damage....but i did take off the front clip....n come to find out i have alot of shit that is missing n i mean alot....ill get more into that later......anyways with the brakes i found the protioning valve took it to the part store they told me to do some ways to fix clean it out and try some other things....but i havent put it on yet but will when i get the chance....before takin the protioning valve off the car i was bleeding the brakes and i notice that there was a screwy thing that looks like you can take off n there is this little hole around that nut....well i had my buddy stick his figure over it and well lets just say i had a strong firm pedal until he takes his figure off.....so idk....can you guys give me some help plz n thank you

just about everything to do brakes for a mclaren GP is in here somewhere.
http://www.tgpforums.com/index.php/topic,3702.0.html

are you the guy with no front clip doing reverse donuts on youtube?
anyway, you must have a leak if your bleeding it and you loose pressure after a short amount of time, also if you dont already know, the ignition key needs to be on when you bleed it.  The brake lights staying on , theres a switch thats a pain in the ass to adjust but its not too bad, once you get it dont pull back on the pedal or it will screwed again.  good luck and welcome to tgpforums.

yes i am

well it sounded good i wouldnt beat on it... spinning the tires in reverse is really bad... the auto trannys on these cars are the weakest point so enjoy them while they last... sounds like the rev limiter is a little higher is it stock chip?

well idk ....ya on the tech she will peg it past 7 grand on the tech so i have no clue...do you have any clue about my braking problem...the tranny in it leaks im sure it need new seals...n i def need to get the filter changed for it to

as far as i kno she is stock i have a cherry bomb were the cat used to be....when i bought her i drove it around for awhile cuz i was so amazed from the power...then i get home n it looked like something was glowing under the car n it wasa the cat...glowing red hot!!!so i had to hack it off and replace it

and my bad about not seeing that lol....and how do you find that switch....and how in the world do you adjust it? we have looked at it but we thought about just getting one out of a a junkd prik but we havent deiceded yet...did you the more info on youtube?...n thanks for welcoming

I wouldn't expect the car to last long if you keep beating on it like that.

lol....you own on you need to lay it down everyonce in awhile.....even if she is beenin sitting i only start her ever so often so i work it in a bit

and is leaking not alot but it does drip......i was told there is alittle ball in the protioning valve that its common they get stuck is that so???thats how i only get one brake and not so much pressure but i still do..

Quote from: blackntan on February 03, 2009, 09:38:39 PM
and is leaking not alot but it does drip......i was told there is alittle ball in the protioning valve that its common they get stuck is that so???thats how i only get one brake and not so much pressure but i still do..

If the proportioning valve is leaking, it's bad and needs to be replaced. GM should still have them available. 88927272
You might want to check with GMpartsdirect.com as it will be cheaper there.

Seriously man, take it easy on the poor car.  It is 19 years old.  "Laying it down" is not throwing it in reverse and redlining the everliving crap out of it... in the middle of winter with a rare car no less.  Beating on such a rare car is frowned upon here, I would suggest that you stop.

Quote from: TGP Nick on February 03, 2009, 09:55:59 PM
Seriously man, take it easy on the poor car.  It is 19 years old.  "Laying it down" is not throwing it in reverse and redlining the everliving crap out of it... in the middle of winter with a rare car no less.  Beating on such a rare car is frowned upon here, I would suggest that you stop.

ok thanks if wat else can you find on there?

By the way...Did you know that you need to bleed the rear brakes with the key in the on position?

Here's a bit more information on the Powermaster III brake system we have: http://www.kazmotorsports.com/tpsgarage/TGP/brakes/powermaster.htm

I don't understand your question.