moisbest42

I'm about ready to burn my car to the ground. So any help is really appreciated. I have a turbo 99 camaro on an ms3pro. I blew it up a few years back and I have really taken my time putting it together and changing things. About a year ago now I tried pretty hard to get the car at the track again. So after a good thrash I had it running, but running rough like it had a big cam. I pull it out of the garage and the brake pedal is hard as a rock. So my gut reaction is vacuum leak. Well since then I have pulled everything off the of the top of the motor and checked everything I can think of. I've used ether around every place that could possibly leak into the intake manifold and found nothing. I have checked every single thing i can think of. I have no idea how a vacuum leak can stump me so bad. Is it possible there is something more going on? I haven't tried new plugs or anything like that to see. But in my mind the only way the car can idle like it is and still have a rock hard pedal is if it's a vacuum leak. Can anyone help me out? Is there something simple I have overlooked or am over thinking? Thanks.

GMCGreg

Brake booster ?
cam retarded?
What's the AFR at when idling?

moisbest42

I've eliminated the booster as the cause. I've pulled the vacuum line to it and plugged it, still the same. Afr is in the 17's at idle. Cam was installed straight up. I know that seems super lean but as soon as you touch the throttle it goes to 13's or 12's. That being said, there's another symptom I forgot to mention, and that is a soon as you whack the throttle it stumbles almost to the point of dying, but if you roll into it slow it'll stumble a little then revs fine.

Y2K_Frenzy

How about buying a smoke tester?

The BallSS

iTrader: (9)

Had this problem a year or so ago and ended up being a broken valve spring that made zero noise and didn't affect the idle either.
Give those springs a look, start carefully spraying brake cleaner around the intake, if the idles jumps, you have a leak.

moisbest42

I checked around the intake with ether, I got no change in the idle. So you had a bad valve spring cause the pedal to be hard?

The BallSS

iTrader: (9)

I did, the broken valve spring brought my idle vacuum down a couple Hg's just enough to affect the power brakes.
I started installing a manual brake kit thinking it was bad and found the broken valve spring after removing the valve cover to get the booster out.
You may have a crack in the intake if using a factory plastic intake or maybe broke a nipple off the back during the swap.

moisbest42

I have a pro flow intake. But I'll for sure check the valve springs when I get home. One of the heads is new, so maybe it's the older one.

moisbest42

It's not the valve springs they're all fine.

GMCGreg

What is the idle vacuum? And what rpm ? Is the idle speed normal or high? Is the combo and tune the same, does it need a retune? Injectors sat for years ? What fuel ? Did they get gummed up from E85? A lot of questions I know but all possibilities

moisbest42

No idea we've the actual in/hg is at idle. Idle speed is about 975. The combo is the exact same and doesn't need a re-tune. I sent the injectors back to id to be cleaned and checked and they're fine. Fuel is e85, and it's fresh.