Annoying little issue.... Options

[dabazied]

Ok, here's what happens. When the car is on and idling, if I pump the brakes, my engine will rev up to about 2k rpm if I keep pumping the brakes..... I'm sure this isnt normal, but was wondering what might cause this. It's not like horrible, just annoying. I like knowing that my pedal to rev the car is always on the far right, not the option between two pedals lol

[Jamchell]

I bet you have a leak in your power assist module, this allows extra air into your manifold when you require assist. The ECU adds fuel to keep AFR in line which in turn causes your idle to rise. Have someone hit the brakes while you listen around the canister you can usually hear the leak.

Also, after you shut off the engine the canister should hold enough vacuum to assist 1 or 2 stomps on the pedal.

This post has been edited by Jamchell: Sep 17, 2009 - 2:45 PM

[solidxsnake]

Ok, here's what happens. When the car is on and idling, if I pump the brakes, my engine will rev up to about 2k rpm if I keep pumping the brakes..... I'm sure this isnt normal, but was wondering what might cause this. It's not like horrible, just annoying. I like knowing that my pedal to rev the car is always on the far right, not the option between two pedals lol

That happens to me too, if I pump/apply the brakes at idle (I'm stuck with a slushbox, so in P or N and not moving), my RPMs go up, although I don't think they go up to 2k, but from 1200 cold-idle or 800ish warm-idle, it still raises in RPM a bit if I pump the brakes.

I have no actual clue on how the braking system works in any car, but I'm under the impression that there is some sort of engine assist to the braking system? Which would explain why the RPMs are affected by braking.

I have ABS in my Celica, if that changes anything.

[Jamchell]

That happens to me too, if I pump/apply the brakes at idle (I'm stuck with a slushbox, so in P or N and not moving), my RPMs go up, although I don't think they go up to 2k, but from 1200 cold-idle or 800ish warm-idle, it still raises in RPM a bit if I pump the brakes.

I have no actual clue on how the braking system works in any car, but I'm under the impression that there is some sort of engine assist to the braking system? Which would explain why the RPMs are affected by braking.

I have ABS in my Celica, if that changes anything.

A temporary small rise in engine speed is normal since the power assist module draws vacuum from the intake. If there is a leak it will be a quite pronounced increase that doesn't equalize very well as you hold the pedal down.

[solidxsnake]

That happens to me too, if I pump/apply the brakes at idle (I'm stuck with a slushbox, so in P or N and not moving), my RPMs go up, although I don't think they go up to 2k, but from 1200 cold-idle or 800ish warm-idle, it still raises in RPM a bit if I pump the brakes.

I have no actual clue on how the braking system works in any car, but I'm under the impression that there is some sort of engine assist to the braking system? Which would explain why the RPMs are affected by braking.

I have ABS in my Celica, if that changes anything.

A temporary small rise in engine speed is normal since the power assist module draws vacuum from the intake. If there is a leak it will be a quite pronounced increase that doesn't equalize very well as you hold the pedal down.

That makes sense. Thanks for explaining that to me