IAC's and drive by wire TB.
08-11-2004, 08:54 AM
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IAC's and drive by wire TB.
Can anyone give me any insight as to how the heck I get my IAC's down after this cam install?
They're 70-80 in P/N, but 130's in gear.
I think it's hanging up my throttle blade, and not letting me go into DFCO. I also have that cruise control effect.
They're 70-80 in P/N, but 130's in gear.
I think it's hanging up my throttle blade, and not letting me go into DFCO. I also have that cruise control effect.
08-11-2004, 12:29 PM
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That's a good question... I'm not sure.
It seems to idle the same with the AC on or off. I only tried the AC once or twice and nothing that happened stood out enough for me to remember.
The idle is liveable, but it does stumble down every once in a while.
I just told Flyer here, that I brought my VE table back to stock. (I was modifying the lower three RPM ranges). I've got my idle speed and Idle Airflow table back to stock too. I modified those two tables by 1.15 - "theoretically" trying to match the raise in idle speed with the raise in air going through the TB.
(That IS what the Idle Airflow table is, right - a virtual 'set screw' for the throttle blade?)
It seems to idle the same with the AC on or off. I only tried the AC once or twice and nothing that happened stood out enough for me to remember.
The idle is liveable, but it does stumble down every once in a while.
I just told Flyer here, that I brought my VE table back to stock. (I was modifying the lower three RPM ranges). I've got my idle speed and Idle Airflow table back to stock too. I modified those two tables by 1.15 - "theoretically" trying to match the raise in idle speed with the raise in air going through the TB.
(That IS what the Idle Airflow table is, right - a virtual 'set screw' for the throttle blade?)
08-11-2004, 12:50 PM
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The 1.15 test I did above didn't work all that bad. The idle is rough from the lope, but strong. I think I may be getting the cruise control effect from my stock stall and it's low stall speed. I thought the thing used to feel a little loose and sloppy way down low, but maybe not.
I'll take the above test down a notch, and see how it does later today.
Another thing - Do you guys notice your spark advance jumping all over the place at idle? Mine has since day one, and never thought about it. Someone in the tuning section mentioned that I'm probably in the Main Spark table at idle. Sure enough, anything over 1.2%TPS is in the main tables. Should I bump that up to something above what my idle TPS is? (somewhere around 8% I think).
I'll take the above test down a notch, and see how it does later today.
Another thing - Do you guys notice your spark advance jumping all over the place at idle? Mine has since day one, and never thought about it. Someone in the tuning section mentioned that I'm probably in the Main Spark table at idle. Sure enough, anything over 1.2%TPS is in the main tables. Should I bump that up to something above what my idle TPS is? (somewhere around 8% I think).
08-11-2004, 12:51 PM
#6
I'd consider those airflow tables more of a combimation of the IAC valve and throttle blade hole.
If you have the cruise effect, your running airflow table is to high. You may find that you need to raise the idle sirflow up a bit, then lower the running table down some.
If you have the cruise effect, your running airflow table is to high. You may find that you need to raise the idle sirflow up a bit, then lower the running table down some.
08-11-2004, 03:10 PM
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Okay... sounds good.
What do you mean by 'running airflow table' though? HPT doesn't have anything labeled like that.
Another thing I just noticed - "Fuel Idle TPS Threshold" is set to 2%. I've never seen the TB blade go down to 2%, so I assume this thing is supposed to be disabled.
What do you mean by 'running airflow table' though? HPT doesn't have anything labeled like that.
Another thing I just noticed - "Fuel Idle TPS Threshold" is set to 2%. I've never seen the TB blade go down to 2%, so I assume this thing is supposed to be disabled.
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08-11-2004, 03:32 PM
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I think I'm picking up on a few "bugs" here.
By what I'm seeing in my timing section, the "Main Spark Table" enabler is set to turn on at that 1.2%. I shouldn't be hitting the base spark tables at all. But the timing that I'm seeing logged, when the throttle is closed and I'm rolling to a stop (not quite idling yet), the data is indeed reflecting that I'm in the base spark table.
I'll have to hit up the HPT forum for this.
By what I'm seeing in my timing section, the "Main Spark Table" enabler is set to turn on at that 1.2%. I shouldn't be hitting the base spark tables at all. But the timing that I'm seeing logged, when the throttle is closed and I'm rolling to a stop (not quite idling yet), the data is indeed reflecting that I'm in the base spark table.
I'll have to hit up the HPT forum for this.
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