Bac cause no idle??
08-10-15, 11:28 AM
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Bac cause no idle??
So my FC will start up and die if I give it gas it will rev up but If I let off it dies. BAC isn't installed but I'm gonna. Is this my issue before I do tho? Stock ECU 1989 Turbo II. Please help and thanks
08-10-15, 01:28 PM
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08-10-15, 01:58 PM
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Bac cause no idle??
Originally Posted by Graham7
So I do not NEED the BAC?
Since you're having issue replacing the BAC may be a good starting point, however it mainly compensates for change in load to keep the car idling. I'm not sure it is your problem. The emissions equipment all served a purpose on a stockish car, a lot of it had more to do with keeping the engine running and idling properly more so than emissions control.
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08-10-15, 02:21 PM
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That's not what I'm saying. No one "needs" the BAC, or any of the emissions equipment for that matter. A lot of us run without it just fine. However, a lot of us also run standalone ECUs which make tuning idle and load easier/smoother. Since you're having issue replacing the BAC may be a good starting point, however it mainly compensates for change in load to keep the car idling. I'm not sure it is your problem. The emissions equipment all served a purpose on a stockish car, a lot of it had more to do with keeping the engine running and idling properly more so than emissions control.
So I just held it at about 2,500 for a little but and I let off and when I did it dropped really far down then can back up to 1,000 for a second the sputtered out. Does that help at all...? Cause if I don't have to buy a BAC I don't wanna. I don't have one on there at all right now
08-10-15, 02:41 PM
#9
The BAC is not an emissions related item unless the car won't start due to a vacuum leak caused by a faulty block off plate and thus the car doesn't start therefor there is no emissions being created. All kidding aside, the BAC is absolutely not an emission apparatus. It's sole purpose is to maintain idle under load, helps in the starting of the car, and assists in the 3k high idle rev which occurs when starting a cold engine.
08-10-15, 02:50 PM
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The BAC is not an emissions related item unless the car won't start due to a vacuum leak caused by a faulty block off plate and thus the car doesn't start therefor there is no emissions being created. All kidding aside, the BAC is absolutely not an emission apparatus. It's sole purpose is to maintain idle under load, helps in the starting of the car, and assists in the 3k high idle rev which occurs when starting a cold engine.
Alright understood. The car has no trouble starting or revving up. Just staying alive on it's own is my issue. I've replaced all vacuum lines and gaskets so that's why I'm lost
08-10-15, 03:00 PM
#11
Have you checked to see if the fast idle cam operation is working as it should or if it has been gutted. The fast idle mechanism should cause a cold started engine to idle close to 1300-1500 rpm and then gradually the idle drops into its comfort zone of 750. The idle should not drop from 3k to 1k. Secondly, only a cold started engine should rise to 3k initially. If you can just play w/the throttle to keep the engine running until it reaches full operating temperature and then turn the car off and a couple of minutes later you try to restart the car and it starts off by reving up to 3k then there is most likely a vacuum leak. Replacing hoses and gaskets alone is not a recipe for removing a possible vacuum leak as it is more involved than that.
08-10-15, 03:05 PM
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Have you checked to see if the fast idle cam operation is working as it should or if it has been gutted. The fast idle mechanism should cause a cold started engine to idle close to 1300-1500 rpm and then gradually the idle drops into its comfort zone of 750. The idle should not drop from 3k to 1k. Secondly, only a cold started engine should rise to 3k initially. If you can just play w/the throttle to keep the engine running until it reaches full operating temperature and then turn the car off and a couple of minutes later you try to restart the car and it starts off by reving up to 3k then there is most likely a vacuum leak. Replacing hoses and gaskets alone is not a recipe for removing a possible vacuum leak as it is more involved than that.
This is also a swap so I haven't ever had it idle. And I will try to do that. The AWS has never kicked in before tho. would the fast idle cam make it not idle at all?
08-10-15, 05:27 PM
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I did it the first time I started it. Should I set it again or no? I set the yellow dot on the crank and the CAS with the pin. Should I do it again?
08-10-15, 06:05 PM
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08-10-15, 06:42 PM
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08-10-15, 08:45 PM
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