when braking the car leaping forward
Welcome to the forum…
Without punctuation, it is hard to know if you are making a statement or have an issue with a question…
Without more info, my crystal ball says your brake rotors are warped…
When you say leaping forward, what exactly are you experiencing?? Is the engine revving up? Does it feel like someone is rear-ending you??
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Or, is your torque converter locking up?
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I had a problem like that on my truck one time, caused by too-high idle rpm. OP, suggest to ask your shop to check your car’s idle rpm.
Check the level of the transmission fluid and the color.
.
Tester
Also at what speed is this happening??
it is speeding up and leaping forward when i try to stop my foot is pushing on the brake
Then the idle air control valve may be defective.
The IAC valve is what controls the engine idle speed anytime your foot is off the accelerator.
Tester
Do you have a CEL (check engine light) on??
If so, then what are the codes???
yes but it doesnot affect the car performant it drives fine i donot know the codes my mecanik know them would cause the car race where the brake are appled
Then why are you asking about when braking the car leaping forward??? Doesn’t seem fine to me…
Then why can’t your mechanic figure out what is wrong with your vehicle if he/she is that knowledgeable??
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Any CEL issue needs to be addressed, and you need to find a better mechanic.
Testor is likely on the right track.
taken it easy i was just looking for information on the problem you have been very helpful thank you
I’m thinking the OP is confusing “leaping forward” with the sensation you get when the brake rotors are warped. It’s not leaping forward, it’s bad brakes.
thank you ihad front brakes donedotknowi if replace the rotors on not iwill ask him monday the rear rotors were a miss do you think that is causing the brakes toslip the engine races foward when i step on the brakes i will start with rear rotors and go from there
I would advise not telling your mechanic what to replace but let him determine what needs to be replaced.
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The engine should not race when you apply the brake, that is the problem, not the rear brake rotors. You need to determine why the engine surges while the car is stopped.
Tell your mechanic that you want that fixed now.
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I will say it again, you need a better mechanic.
The guy you are using, as far as I can determine from your comments, has not stated what the codes are causing your CEL to be on.
Leaping forward, engine racing—-is not driving fine.
Apparently you do not live in a state, such as Florida, that does not require safety or emission testing. A CEL would not pass inspection in states that do require testing.
Bite the bullet, get the car diagnosed, expect to pay a diagnostic fee, and repaired by a competent shop.
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Read my very 1st post, the 1st reply, I said my crystal ball says your rotors are warped… BUT the OP is saying that the engine is racing (revving up)… So either the OP has a giant foot and it hitting the gas at the same time as the brake then there is a problem (safety also) that requires repair…
That being said , now I am wondering if the OP is a left foot braker and pushing with both feet… or just simply NOT sliding his/her foot all the way off the gas pedal while depressing the brake pedal…
But if we new why the CEL was on it would help shed a little light on the situation…
Either way the OP needs to find a competent mechanic as already mentioned…
Wondering, could a faulty brake booster (split diaphragm etc) cause an increase in engine speed when the brake pedal is pushed? The booster has a good size path into the intake manifold, an air leak that got into the engine there could cause the engine rpm to rapidly increase. OP might ask their mechanic if that’s a possible explanation.
I was measuring the intake manifold vacuum on my Corolla one time, had to remove a rubber plug so I could install my vacuum meter there. when I removed that plug the engine rpm immediately increased. Not dramatically, but noticeably. The plug was covering a very small opening.