2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

O.o wtf is this?

Thread Tools
 
Search this Thread
 
Old Nov 2, 2007 | 02:36 PM
  #1  
cyberxn's Avatar
Thread Starter
Remove this account
Tenured Member 05 Years
 
Joined: Sep 2006
Posts: 373
Likes: 0
From: REMOVE MY ACCOUNT
O.o wtf is this?

i cleand the BAC. via means of Carb cleaner.
Ive done this befor.
NOW when the car trys to Idle it go's
Broom Blah broom Blah...
I have video of it with sound... but i gotta try and get to work soon.
when i Unplug the BAC.. it idles out... but im not sure if INFACT that is the problem.
LEmme know... ill post the video when i can
Reply
Old Nov 2, 2007 | 02:44 PM
  #2  
Nick_d_TII's Avatar
Rotary Freak
Tenured Member 20 Years
iTrader: (6)
 
Joined: May 2002
Posts: 1,620
Likes: 6
From: Beaverton, OR
You could have toasted your o2 sensor... I'm not sure, but thats usually what causes that rolling idle problem... broom blah.. maybe..
How did you clean it? just spray the out side?
Reply
Old Nov 2, 2007 | 03:09 PM
  #3  
cyberxn's Avatar
Thread Starter
Remove this account
Tenured Member 05 Years
 
Joined: Sep 2006
Posts: 373
Likes: 0
From: REMOVE MY ACCOUNT
sprayd the inside of the intake where the bac is located. then removed it cleand it checked it.... seemd fine.. ran ok for about 30 secs.... then broom blah death
Reply
Old Nov 2, 2007 | 03:51 PM
  #4  
cyberxn's Avatar
Thread Starter
Remove this account
Tenured Member 05 Years
 
Joined: Sep 2006
Posts: 373
Likes: 0
From: REMOVE MY ACCOUNT
is there really a need to having it plug'd in?

I know they sell blockoff plates for it... but would there be any loss in power with it unplugd?
Reply
Old Nov 2, 2007 | 07:32 PM
  #5  
lax-rotor's Avatar
Technician
Tenured Member 10 Years
iTrader: (1)
 
Joined: Aug 2006
Posts: 1,008
Likes: 1
From: Virginia
I think it's just for emissions.
Reply
Old Nov 2, 2007 | 07:56 PM
  #6  
NZConvertible's Avatar
I'm a boost creep...
Tenured Member 05 Years
 
Joined: Jan 2002
Posts: 15,608
Likes: 8
From: Auckland, New Zealand
Originally Posted by Nick_d_TII
You could have toasted your o2 sensor... I'm not sure, but thats usually what causes that rolling idle problem...
Where did you hear that crap? The O2 sensor has nothing to do with idle control and could never cause this.

Originally Posted by cyberxn
is there really a need to having it plug'd in?
If you want proper idle speed control, yes. The rolling idle is the ECU trying to compensate for something being wrong, like a vac leak, TPS out of adjustement or idle speed set too high. It's not caused by the BAC valve.

...but would there be any loss in power with it unplugd?
No.

Originally Posted by lax-rotor
I think it's just for emissions.
It has nothing to do with emissions. If you don't know, don't guess...
Reply
Old Nov 2, 2007 | 08:18 PM
  #7  
cyberxn's Avatar
Thread Starter
Remove this account
Tenured Member 05 Years
 
Joined: Sep 2006
Posts: 373
Likes: 0
From: REMOVE MY ACCOUNT
thankx for all the help.. ill check into the vac and ecu
Reply
Old Nov 2, 2007 | 08:24 PM
  #8  
NZConvertible's Avatar
I'm a boost creep...
Tenured Member 05 Years
 
Joined: Jan 2002
Posts: 15,608
Likes: 8
From: Auckland, New Zealand
It's unlikely the ECU is the problem.
Reply
Old Nov 2, 2007 | 08:35 PM
  #9  
cyberxn's Avatar
Thread Starter
Remove this account
Tenured Member 05 Years
 
Joined: Sep 2006
Posts: 373
Likes: 0
From: REMOVE MY ACCOUNT
ok well I've just lookd into the vac lines.. sprayd carb cleaner around the lines.. and no change in idle with the bac unplugd.... I'm thinking the bac or the tps.. even though it was just told to me one or the other.
anyway of checking the tps?
Reply
Old Nov 2, 2007 | 08:47 PM
  #10  
NZConvertible's Avatar
I'm a boost creep...
Tenured Member 05 Years
 
Joined: Jan 2002
Posts: 15,608
Likes: 8
From: Auckland, New Zealand
The BAC valve can't cause a hunting idle by being broken or defective. If it breaks it simply doesn't work and acts the same as when it's unplugged. It's controlled by the ECU, which resonds to all the engine input sensors. The sensor with the most impact on idle quality is the TPS, so make sure it's set right (search for the many how-tos). In my experience, if the TPS isn't set properly and the idle it set too high with the throttle stop screw, the ECU can go into a nasty feedback loop trying to get the idle speed right, causing the idle speed to hunt.

Disconnect it if you want, but that won't fix the cause of the problem, only one of the symptoms.
Reply
Old Nov 2, 2007 | 09:51 PM
  #11  
cyberxn's Avatar
Thread Starter
Remove this account
Tenured Member 05 Years
 
Joined: Sep 2006
Posts: 373
Likes: 0
From: REMOVE MY ACCOUNT
ok. so how do I fix "the problem" o.o?
Reply
Old Nov 3, 2007 | 12:53 AM
  #12  
mike(13b)'s Avatar
Newbie
 
Joined: Sep 2007
Posts: 4
Likes: 0
From: Caldwell
my bac system isnt working, and i dont have a shity idle,
it definatly feels like it has lost power tho... that thing pisses me off every time i look at it, my air pump also dosnt work
Reply
Old Nov 3, 2007 | 01:33 AM
  #13  
AUGieDogie's Avatar
Rotary Freak
Tenured Member: 20 Years
iTrader: (4)
 
Joined: May 2003
Posts: 1,587
Likes: 4
From: seattle
Originally Posted by mike(13b)
my bac system isnt working, and i dont have a shity idle,
it definatly feels like it has lost power tho... that thing pisses me off every time i look at it, my air pump also dosnt work
Are you sure your bac isn't working. Unbolt it, you cant unscrew the hose part with a philips head so you don'thave to take off the watter hose. Then set the bac somewhere solid on your engine. Turn the ignition switch so all your idiot lights come on. Then listen/look at the BAC. You should see and hear it vibrating. You can also stick your finger in there to see if its working. If it IS vibrating, then obviously your BAC is working. Put it back on. If its not vibrating, let us know and we will let you know how to fix it.

I would bet its not the BAC, car runs just fine without it. just doesn't idle worth a ****.
Reply
Old Nov 3, 2007 | 01:46 AM
  #14  
NZConvertible's Avatar
I'm a boost creep...
Tenured Member 05 Years
 
Joined: Jan 2002
Posts: 15,608
Likes: 8
From: Auckland, New Zealand
Originally Posted by mike(13b)
my bac system isnt working, and i dont have a shity idle,
it definatly feels like it has lost power tho...
Completely unrelated.
Reply
Old Nov 3, 2007 | 05:06 AM
  #15  
HAILERS's Avatar
HAILERS
Tenured Member 10 Years
 
Joined: May 2001
Posts: 20,563
Likes: 27
From: FORT WORTH, TEXAS,USA
Pull the plug off the bac and look at the sockets inside the harness plug. See if one or both sockets are pushed back. In other words not locked in. IF the wires are making a flakey connection with the pins in the bac, then that can cause a rapid rise/fall of the rpms at idle.

Or try this. Next time it does this rapid rise/fall in rpms at idle, go to the bac and shove up on the bac plug AND or the wires of the plug and see if there is a change in the condition. IF the idle changes, there there is flakey connection of the bac plug/wires causing the problem.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Jesse Cardinal
Introduce yourself
0
Sep 20, 2015 06:31 PM
t-von
3rd Generation Specific (1993-2002)
9
Sep 10, 2015 01:56 PM
EfiniGirl
Haltech Forum
2
Sep 1, 2015 09:31 PM
Wolf_
Single Turbo RX-7's
3
Aug 11, 2015 04:23 PM




All times are GMT -5. The time now is 04:00 PM.