8747 ecm usng $4F need a/c control help
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Car: 85 chevy k5
Engine: TBI 350 H.O.
Transmission: 700r4
Axle/Gears: 4.10
8747 ecm usng $4F need a/c control help
i have the 1228747 HD ecm in my chevy K5. i had a company trying to tune chips for me and they couldn't get it running very well. so i ventured out and have started tuning for myself. now i totally understand why they couldn't. there's no way to know what to do without having the actual vehicle.
anyways, they had a burn for me that allowed the ecm to up the idle when you'd turn the a/c on. i would like to have it bump up the idle by about 200 rpm since my a/c compressor is now converted to on board air. but in the $4F mask i can't find any a/c controls for the 8747 ecm....is there another mask i can use?
what do i need to change in the chip to get the idle to come up?
winaldl comes up with "no a/c requested" but i don't know how to change that.
im using tunerpro, if you can help me out
anyways, they had a burn for me that allowed the ecm to up the idle when you'd turn the a/c on. i would like to have it bump up the idle by about 200 rpm since my a/c compressor is now converted to on board air. but in the $4F mask i can't find any a/c controls for the 8747 ecm....is there another mask i can use?
what do i need to change in the chip to get the idle to come up?
winaldl comes up with "no a/c requested" but i don't know how to change that.
im using tunerpro, if you can help me out
Last edited by rokcrawlin85; 04-17-2011 at 04:15 PM.
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Re: 8747 ecm usng $4F need a/c control help
Looks to be this value:
LD5ED FCB 0 ; DIFF RPM FOR A/C ON (RPM/12.5)
A/C status input should be on pin B8. Set +12 volts to it to change the A/C status.
RBob.
LD5ED FCB 0 ; DIFF RPM FOR A/C ON (RPM/12.5)
A/C status input should be on pin B8. Set +12 volts to it to change the A/C status.
RBob.
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Car: 85 chevy k5
Engine: TBI 350 H.O.
Transmission: 700r4
Axle/Gears: 4.10
Re: 8747 ecm usng $4F need a/c control help
in the constants or the table values? i can't find it in either one...
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Re: 8747 ecm usng $4F need a/c control help
RBob.
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Re: 8747 ecm usng $4F need a/c control help
i have to idea how to add definitions... can you help? step by step maybe...
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Re: 8747 ecm usng $4F need a/c control help
RBob.
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