Source code experts...I need help figuring this out...
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From: 600 yds out
Car: Bee-Bowdy
Engine: blowd tree-fity
Transmission: sebin hunnerd
Axle/Gears: fo-tins
Source code experts...I need help figuring this out...
I'm trying to tune in my friends T/A. He has: ZZ4 shortblock, 224/230 .500/.510 cam, Sportman II heads, 2" TBI w/ 90pph injectors, run by a 7747 ECM.
When you first start the car it seems to run fine. If you take it out of P or N then the engine starts surging and IAC maxes out every time. I cannot figure out why it would do this.
I found some interesting stuff in a hack. I hope this is enuf info. If not I'll post the entire thing. Specifically where it breaks (I think) and says if there is an overflow (?) then force to max.
TIA
When you first start the car it seems to run fine. If you take it out of P or N then the engine starts surging and IAC maxes out every time. I cannot figure out why it would do this.
I found some interesting stuff in a hack. I hope this is enuf info. If not I'll post the entire thing. Specifically where it breaks (I think) and says if there is an overflow (?) then force to max.
TIA
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
The code is not the problem. Here is the snippet:
At E0F8 the EPROM value at LD5C1 is being added to the value in
reg A. If an overflow occurred then load reg A w/255. The BCC
is a branch carry clear. Common stuff.
With the cam, heads, TBI, and injectors you'll need to do some
serious tuning. May need more idle timing, open loop idle,
more throttle plate opening, richer AFR commanded for idle,
higher idle speed. May even be a torque convertor problem.
RBob.
Code:
E0F6: STAA L00E4 ; LK'ed UP STEPS
E0F8: ADDA LD5C1 ; 25 STEPS, INT NON VOL RAM FAIL FOR A/C
E0FB: BCC LE0FF ; BR IF NOT OVERFLOW
; ... el
E0FD: LDAA #255 ; FORCE MAX VALUE
E0FF: LE0FF STAA L00C1 ; INIT MOTOR POSIT AFTER RESET reg A. If an overflow occurred then load reg A w/255. The BCC
is a branch carry clear. Common stuff.
With the cam, heads, TBI, and injectors you'll need to do some
serious tuning. May need more idle timing, open loop idle,
more throttle plate opening, richer AFR commanded for idle,
higher idle speed. May even be a torque convertor problem.
RBob.
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