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Old 02-12-2018, 02:21 PM   #1  
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Default Hot start throttle hang

hi guys. Whenever I hot start my car, the throttle always seems to hang for 1 sec when shifting. It wont do it if the car is warmed up from a cold start. Ideas?
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Old 02-13-2018, 09:26 AM   #2  
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Try less crank to run taper time.
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Old 02-13-2018, 12:22 PM   #3  
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Ok ill try that. Thanks Matt.
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Old 03-20-2018, 12:58 PM   #4  
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Update. That helped with inital startup. But when I am driving the car there is still throttle hang after a hot start. This started happening after the skunk 2 tb install. And yes, I already re-drilled the throttle spring hole.
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Old 03-20-2018, 03:03 PM   #5  
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Quote:
Originally Posted by MiataMan00 View Post
Update. That helped with inital startup. But when I am driving the car there is still throttle hang after a hot start. This started happening after the skunk 2 tb install. And yes, I already re-drilled the throttle spring hole.
Drill it again. Drill it harder. Drill it with fire!

Okay, maybe don't drill it again. Ensure your throttle cable is not kinky and that there is nothing in the way of wiring harnesses or insulation interfering with the cable inside the firewall.
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Old 03-20-2018, 04:57 PM   #6  
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Wouldn't decreasing IAC initial values table in affected cells help this? Presumably the top row where you're highest CLT/IAT numbers are.

*Sorry if that's a dumb suggestion. I suck at idle tuning and I'm still trying to grasp how everything works together.*
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Old 03-20-2018, 05:18 PM   #7  
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Quote:
Originally Posted by sixshooter View Post
Drill it again. Drill it harder. Drill it with fire!

Okay, maybe don't drill it again. Ensure your throttle cable is not kinky and that there is nothing in the way of wiring harnesses or insulation interfering with the cable inside the firewall.
Itís not that because it only does it after hot starts. Running it from a cold start itís fine.
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Wouldn't decreasing IAC initial values table in affected cells help this? Presumably the top row where you're highest CLT/IAT numbers are.

*Sorry if that's a dumb suggestion. I suck at idle tuning and I'm still trying to grasp how everything works together.*
wouldnt help. Itís not an idle thing. It does it between shifts.
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Old 03-20-2018, 06:03 PM   #8  
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Dashpot adder too high?
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Old 03-22-2018, 04:15 PM   #9  
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I dont think so because the throttle dips when entering idle. Of anything I need to raise it
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Old 03-22-2018, 04:16 PM   #10  
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I dont think so because the throttle dips when entering idle. If anything I need to raise it.
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Old 03-22-2018, 04:55 PM   #11  
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$20 says a datalog will show it's not actually in closed-loop idle mode when it hangs. The valve hangs open because the RPM is outside the bounds where CL idle can activate, and so it hangs there forever. Blip the throttle and the revs will drop on the way down, CL will activate, and it will come down to a normal idle.

Reduce the max idle DC% or reduce the hot idle initial duty cycle.
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Old 03-23-2018, 12:12 AM   #12  
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It will come down to idle rpm every time. Its just when shifting, the RPMs dont drop when clutch is depressed. it hangs for .5-1 sec before dropping down. Its not an idle issue.

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