Timing and running rich?
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Joined: Jul 2009
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From: Silicon Valley
When you get the idle bouncing around, it's the ECU trying to compensate for an inconsistency. The BAC is ECU controlled, and it'll change the amount of air it allows in, which increases/decreases idle speed. In addition to a vac leak or TPS issue, a bad AFM can also screw with the idle. I have an extra NA AFM that will make it idle rough and stall if I plug it in. There are resistance values listed in the FSM for it too.
As far as where to look for vac leaks, there are a ton of places. Any of the locations with gaskets or the larger hoses going into the manifold would be the most likely areas.
As far as where to look for vac leaks, there are a ton of places. Any of the locations with gaskets or the larger hoses going into the manifold would be the most likely areas.
Wiggled wires to connector that plugs into BAC and that didn't seem to do anything.
Removed BAC and cleaned it with carb cleaner. Didn't look like it needed cleaning.
Turned Allen screw on the front end of BAC that is on the same side as the connector to see if I could smooth RPM out. That actually made things worst.
The cars idle RPM is to high (1300-1500). Turning the air adjust screw doesn't help much. I can't move idle down below 1000 unless I completely turn the Allen screw completely into the BAC. In any case I'm now getting oscillations in RPM at any setting and they are more pronounced. Also, there seems to be an intermittent hissing type sound coming from the BAC.
Furthermore, turning the variable resistor when trying to set idle does not seem to do anything.
It seems like I need a new BAC. Is there a way to acceptably run the car without the BAC being operated automatically by the electronics and causing ECU issues?
Thread Starter
Full Member
Joined: Jul 2009
Posts: 82
Likes: 0
From: Silicon Valley
TPS is fine (checked resistance throughout range of motion and OK).
Wiggled wires to connector that plugs into BAC and that didn't seem to do anything.
Removed BAC and cleaned it with carb cleaner. Didn't look like it needed cleaning.
Turned Allen screw on the front end of BAC that is on the same side as the connector to see if I could smooth RPM out. That actually made things worst.
The cars idle RPM is to high (1300-1500). Turning the air adjust screw doesn't help much. I can't move idle down below 1000 unless I completely turn the Allen screw completely into the BAC. In any case I'm now getting oscillations in RPM at any setting and they are more pronounced. Also, there seems to be an intermittent hissing type sound coming from the BAC.
Furthermore, turning the variable resistor when trying to set idle does not seem to do anything.
It seems like I need a new BAC. Is there a way to acceptably run the car without the BAC being operated automatically by the electronics and causing ECU issues?
Wiggled wires to connector that plugs into BAC and that didn't seem to do anything.
Removed BAC and cleaned it with carb cleaner. Didn't look like it needed cleaning.
Turned Allen screw on the front end of BAC that is on the same side as the connector to see if I could smooth RPM out. That actually made things worst.
The cars idle RPM is to high (1300-1500). Turning the air adjust screw doesn't help much. I can't move idle down below 1000 unless I completely turn the Allen screw completely into the BAC. In any case I'm now getting oscillations in RPM at any setting and they are more pronounced. Also, there seems to be an intermittent hissing type sound coming from the BAC.
Furthermore, turning the variable resistor when trying to set idle does not seem to do anything.
It seems like I need a new BAC. Is there a way to acceptably run the car without the BAC being operated automatically by the electronics and causing ECU issues?
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