Hey Pete==Have the brake booster checked out. The diaphragm may have a leak. GoodlukcJoe
just took it out for a test drive and it only happens when car is at operating temp not when cold any ideas?
try flushing out the fuel system. stuff builds up in there and it doesn't run as clean and as well as it should. also anylost power the car had wil be restored and your gas milage should improve. i have a 92 and it did the same thing
jay
HeadlineIt's either a vacuum leak (check all hoses) or it's probably the Idle Air Control Motor (or IAR it's sometimes called) needing cleaning. These cars and other J-body cars too, are known for this problem, in fact not just GM cars either. My 92 3.1 V6 Sunbird does the same thing about every 5000-6000km, maybe even less. It's a little motor (usually black) with a 3 wire connector on it right near the Air Filter hose and throttle body and it has 3 vacuum lines in a row coming out the other side of the plenum it's attached to. A Haynes or Chilton manual will not show you the location of this motor and when you look it up and it usually says to take it to a mechanic because it needs to be hooked up to a computer. It doesn't in most cases (just disconnect the battery and reconnect when job is finished to reset the computer so it can "re-learn".) Use degreaser or Isopropyl alcohol or lighter fluid (something powerful that evaporates) there is a special spray too that my mechanic uses, anyway, submerge the motor, and don't worry about submersion it's a sealed motor anyway, shake out the excess (you'll see how dirty the excess fluid is.) wipe off and let cleaner evaporate/dry (unscrew the pintle and spring before cleaning so the cleaner gets right down in there, clean the spring and pintel too while your at it). Then reattach it to it's plenum (make sure to put the rubber O-ring back onto the neck of the motor)! If that doesn't work, take off the plenum the motor came off of, clean it and put back in with a new paper gasket (the original one is plastic and tends to get brittle from heat, mine broke apart in my hands after removal). Line the whole gasket with a thin layer of high-temp silicone for a good air-proof seal. If the motor is faulty (you can test it by unscrewing the motor out of it's plenum and turning the key, then turning on the air conditioning. A/C causes the pintel to move in and out, although I guess anything requiring more air like revving the engine would work too. if it's faulty, get a new one, they are usually only about $20. Don't worry if it does this "erratic idling" a little again at first after cleaning, the computer is just re-learning and adjusting accordingly. You will notice (on the RPM needle) that when the idle goes wacko again, the computer and motor together will "flick" the RPMs back down to where they are supposed to be (I use the word flick because the needle will literally snap back to about 600-800 rpm when the engine starts to rev. to high or too low). This is how you know it's fixed. After the computer learns for a few drives and finds a happy medium, your idling at a stop light or when applying the brakes should be perfect. The only difference between this method and a mechanic is there is almost no computer re-learning (they adjust it to the happy medium by computer instead of letting the computer retrain itself.) The main thing is the little motor is clean and that's the most important part. (Well, for a little while anyway, till it gets dirty again!) Isn't this what air-filters are supposed to filter out? :)STICKING BRAKE CALIPER
Are the brakes right and is the e-brake not sticking?
Normally this is caused by warped brake rotors.
I would advise bringing your car to a mechanic as quickly as possible. Your brakes could fail. This puts you at a high risk for injury or even death.
excessive shaking when applying brakes points to brake rotars being out of round, cracked or warped. have rotors machined
This could be for a few reasons, but if they are getting hot without you applying them, I would suggest that they are sticking and causing the pads to rub on the discs, or if they are drum brakes, the shoes on the drums. If they are only getting hot as a result of using the brakes, I would suggest checking that the brakes are balanced properly, and that the front brakes are not doing all of the work/ or that the back brakes are working at all.
brake pads could be worn out. would it be safe to drive for now if the front brake pads are ok?
Possibly warped brake rotor/worn brake pads. Get this checked out.
You would adjust the brakes on a vehicle with abs brakes the same way you would adjust the brakes on a vehicle without abs brakes.
This is a two part answer, as USGA handicap would show that applying brakes on a golf course when riding a cart, would be 100%. Otherwise your cart would crash. If you are walking, then braking would not apply so it would be 0%
Try having your tires balanced and rotated. I used to have a car that would shake very bad when applying the brakes and I did everything you did. Then a guy told me to have my tires balanced and rotated and it fixed it until the tires became unbalanced again.
It is called a brake booster. It is a vacuum operated servo which assists you in applying enough force to the brakes to stop the car safely. Without it the pedal force required would be many times more