What the hell happened? & Exhaust install questions

Ok, last night I just got done installing a BBK o/r H, and Flows catback, I also disconnected the battery for about 6 hours, when I went to start her up she sounded fine, seemed to idle a little higher and take a little longer to drop, but that may just be me looking for stuff to go wrong, backed her out of the garage fine and as I was coming up to the end of the street, at the stop sign, the car idle like ****, bounced to around 800 then dipped to 300 and almost died, then cam back to life, I went around the block, punched it once and it felt ****ty, felt even slower, then went home and called it a dissappointing night.

So first, what happened to my idle, was it disconnecting the battery that tells the car to relearn, or something like that?

Why did it feel slower than before?

I do have an exhaust leak, could that be the problem?

Second, there is some sort of tube that runs parallel with the passenger side stock H and then runs up to some sort of air lines ( it's on this page as fig.3 http://www.stangnet.com/tech/shorties/shortyheader.html) I think it's the air injection, but the instructions call it a vacuum line, I just unhooked it and left it, could that be my problem that the idle jumped like that? Because there is no vacuum going on and it is a vacuum line according to the instructions.

Thanks to nayone who replies.

GRGT1994 said:

After having the battery unhooked that long, you should let it idle for a good 5 minutes to give the compute time to "relearn" its idle. Turn off all accessories while it idles (lights, radio, etc.).

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Will do

wytstang said:

First hook up that vac line that just may be your problem. If that doesn't help you may have damaged the o2 sensors during the install and no you may not get a CE light either most don't ( I didn't).

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Didn't get the CE, was reallu careful of the 02s, thing is the line I disconnected cannot be reconnected as it was part of the OE H-pipe, instead of emptying or sucking right before the second pair of cats, it is just emptying or sucking from the engine bay.

maypo59 said:

You now are hopefully breathing better (or, your car is, anyways) If your MAF needs cleaned, it will show up, could be your problem.

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MAF shouldn't need cleaning, and even if it did you could set your watch to the idle I had before hand. But will take a peek

squall9393 said:

One is on the EGR and I forget where the other is but they are red and green lines with black boots on the end of them.

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I thought the EGR ran straight from the header to the TB. I'm confused

squall9393 said:

Ensure that they are either connected or- in the case that you remove the smog pipe- they are plugged up. Also check your air intake for leaks as well but go to the vacuum lines first since you were messing with the exhaust.

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When you sat smog pipe, do you mean the pipe that pumps air into the stock exhaust system? If so, won't plugging it cause daamage to the pump because it's pumping into a dead end and the plug will just pop off?


Thanks for the help, sorry if I sound like an idiot, I'll go try to check it out right now.


Also the BBK h-pipe comes with a little tube to accept the air injection and without that being there, their is an exhaust leak, shiort if welding it, whuch will be done shortly, is there anything I can plug it with for the time being?

Thanks again!!

squall9393 said:

That's not part of the EGR. Are you talking about the smog line that runs from the cats to smog pump and has the two vacuum lines attached to it SWYZ721?

Oh wait. I saw the picture. Yeah those need to be plugged along with the ones behind the intake manifold if they are unconnected.

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Ya that's it, plug em? Cool. Got any advice in what to use?

EDIT: actually, if you look at fig. 5 on the link I posted, it's pointing exactly to it, that is what's disconnected and open to the atmosphere.

wytstang said:

I think he when he says they need to be plugged he means connected because I'm pretty sure they need to be.

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To what though? The stock piece is gone and as far as I know all it does is pump air, that wouldn't affect the idle, would it?