89 5.0 5-spd coupe w/ high miles & stock motor. Recently when accellerating hard and reving above 3-4000 RPM the brake light temporarily comes on the dash. If I lift or upshift the light goes out, only to repeat if I get back into the throttle hard. Any suggestions for what to check?
Is the car a standard ? Sticks come with a shift light on the dash, close to the brake light. Been a while since I had a dash of one of those, but it sounds like there is a crossed wire on the shift light.
No Fox Mustang comes with a shift light built in.... Most likely the connection which lies on the ebrake under the rear center console has come loose and the force of the car accelerating is causing the terminals to touch and thus the light comes on. Check out the ebrake switch
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Cardinal Red '88 GT 5 speed, Cobra Upper/Lower, Dynomax complete Super-Turbo cat-back system, Turbo Coupe Rear 10" discs, 3:73 gears, SN95 Master Cylinder, Summit Racing adjustable proportioning valve, Spec Stage II kevlar clutch, steeda adjustable cable/quadrant, 73mm front calipers, P.A. Performance 130 amp alternator, 99 Contour Electric Dual Fans, Battery relocated, rebuilt 91 T-5, Mass Air conversion
I guess it could be the e-brake switch in the center console. I had to remove the console a couple weeks ago to pull the dash for a heater core change. I'll take a look at the switch.
I was thinking something vaccum related. The booster is aided by vaccum and at WOT you wouldn't have any in the manifold. Any thoughts or am I way off base?
They most definately did have a factory shift light, but upon a little research it was only put on the 4 cyl and v-6 standards. My car was a 4 cyl standard, and when I dropped the 302 in I put a C-5 behind it. I hooked the factory tach back up after setting it to the v-8 setting, and I thought it was funny because the shift light would still come on sometimes even though it was an automatic. Also you had to push in the clutch to start it, even though it wasn't connected to anything.
it could definitely be low brake fluid too, if you still have a stock style master with the float in it. They definitely do NOT run on air, only semis and buses run on pneumatic brake systems really.
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Cardinal Red '88 GT 5 speed, Cobra Upper/Lower, Dynomax complete Super-Turbo cat-back system, Turbo Coupe Rear 10" discs, 3:73 gears, SN95 Master Cylinder, Summit Racing adjustable proportioning valve, Spec Stage II kevlar clutch, steeda adjustable cable/quadrant, 73mm front calipers, P.A. Performance 130 amp alternator, 99 Contour Electric Dual Fans, Battery relocated, rebuilt 91 T-5, Mass Air conversion
Thanks guys. I was low fluid. The resevoir was stained so it looked full but upon futher inspection it was low. Problem solved. Now I just need to start figuring out how it got low in the first place.
Low fluid level can be an indication of worn out brake pads. As the pads wear the pistons move farther out of the caliper. It doesn't mean the pads are totally worn out. I would definately check out the front pads and rear shoes.
Make sure to inspect the rest of the brake system for leaks, including the rear wheel cylinders. Peel the outer boot back on the rear cylinders and make sure it's dry. If there is fluid there the cylinders will have to be rebuilt or replaced.
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95 GT Coupe, FRP B spring kit, Bullitt Wheels, Hurst short throw shifter, SVO Cobra Intake, X303 Aluminum Heads, Cobra Roller Rockers 1.7, Equal Length Ceramic Headers, BBK H Pipe, FRP Low Restriction Exhaust, Bullitt Calipers and 13" rotors. American Racing CAI.
Brake light comes on at High RPM??? 
