Preface: I was having high and surging idle problems since I got the car running so I went ahead and replaced most the vacuum lines, then removed and blocked the ACV and BAC.

Once the car warms the idle drops down near the 300-400 mark and gets to that "seems like it is going to stall" point. Although it does not stall and it does give the exhaust an interesting pulsing idle, but I could see this being a nuisance.

I know that BAC effects idle but is this a normal byproduct of removing the valve?

 

The main reason for the existence of the BAC is to keep the idle from dropping below 750 rpm.

 

Alright. I thought it was only to keep it above 750 under extra load. Since I don't have AC running, PS working, or air pump I figured it would stay somewhat normal.

Thanks.

 

If every aspect of the engine was working as it should then the idle should be right at 750 rpm but since your car is not working exactly as it did when it was a pup the BAC helps to make up for this difference. You might be able to adjust the Idle Adjust Screw on top of the Dynamic Chamber (throttle body) to help increase your current idle speed but I doubt you'll be able to make up the total difference from what it is now to how it should be. The BAC is activated by the ECU and it causes the BAC go full open upon start up so this feature helps to start the car as well.

 

put the BAC valve back on. you don't need the coolant hose if that's what you were really trying to eliminate.