Raising Idle 99 Bonne
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Raising Idle 99 Bonne
Ok guys. I've noticed in my car that when my voltage drops to the red zone, right before it, my idle drops to about 500. When I'm in park, the idle is about 1000. Is there any way to raise the idle when I'm in gear? I feel like that'* what'* causing my voltage to drop to where it shouldn't be. It mainly drops when I hit the brakes. If I put her in neutral, it goes back to normal. If I rev it in drive, it goes back to normal as well. I'm really worried. I feel if I raise the idle, everything will be fine. I don't want to put my subs in without fixing the problem first.
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The idle is changed in the PCM. But I don't believe that is your problem. I would guess your idle drops because your voltage drops first. I would be checking the cable between the alt and the battery, and the battery to ground. You also may want to check the alt. I think this mod will work on your car. Look at the alt plug, if you have 2 wires yes, if 3 wires, no. https://www.gmforum.com/showthread.p...ght=sense+wire
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The idle is changed in the PCM. But I don't believe that is your problem. I would guess your idle drops because your voltage drops first. I would be checking the cable between the alt and the battery, and the battery to ground. You also may want to check the alt. I think this mod will work on your car. Look at the alt plug, if you have 2 wires yes, if 3 wires, no. https://www.gmforum.com/showthread.p...ght=sense+wire
This one is for a Grand Prix, but then again, there'* no Bonneville section on there.
http://www.zzperformance.com/grand_p...=517&catid=107
And
http://www.zzperformance.com/grand_p...ts1.php?id=178
Would it be bad if I added both? I need to fix this problem ASAP.
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No on the first link, not sure on the second link. Basically it'* a new battery to alt cable. The pre 2000 Bonnevilles don't have the alt sense wire and the voltage runs a little lower. That mod adds about half a volt or so. The idle drops because the voltage drops. Weak spark. The sense wire mod is easy if you follow the write up. Your simply cutting off the old plug and soldering in a new plug with 3 wires. Then connect one wire by the fuse box. Done. It makes the alt work just like a 2000+
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No on the first link, not sure on the second link. Basically it'* a new battery to alt cable. The pre 2000 Bonnevilles don't have the alt sense wire and the voltage runs a little lower. That mod adds about half a volt or so. The idle drops because the voltage drops. Weak spark. The sense wire mod is easy if you follow the write up. Your simply cutting off the old plug and soldering in a new plug with 3 wires. Then connect one wire by the fuse box. Done. It makes the alt work just like a 2000+
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I'll see if I can find one of my friends to help me. A bunch of my friends are now certified mechanics which is a plus. lol
#9
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RPM drops, which slows the alternator and the voltage dropping is more common the cars.
This is because at 500-600 the pcm turns off the field of power to keep the alternator producing.
The best way to bump idle is through the pcm. However there is a set screw on the side of your TB that could be used to do this as well.
This is because at 500-600 the pcm turns off the field of power to keep the alternator producing.
The best way to bump idle is through the pcm. However there is a set screw on the side of your TB that could be used to do this as well.
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The problem being related to brake application leads me to believe there may be a vacuum issue also. Double check all connections and hoses.