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Old 06-02-2011, 01:24 PM   #1
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Default how to get rid of extra fuel coming off throttle?

I have an issue coming off the throttle where I see the wideband read out down to the 10 AFR's

I'm wondering if this an issue with the VE table or more likely the injectors being held open to long compared to how fast the engine is reacting

Here is a view of what I'm talking about

I will throw up a log and a MSQ as well

overrun is setup to come on 2 seconds after it meets the requirements



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Old 06-02-2011, 02:07 PM   #2
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There's a throttle enrichment setting that you can have a % of fuel on decel less than 100. You can try starting by entering 90 or 70 or something in there and see if it helps.
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Old 06-02-2011, 02:16 PM   #3
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honestly, your PW drops as your vacuum increases, so much so that the AFRs eventually go really lean before overrun even kicks on.

You can see where overrun kicked on where the PW spiked down to 0 for a split second, that's the only time you weren't injecting fuel.
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Old 06-02-2011, 07:26 PM   #4
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Quote:
Originally Posted by Braineack View Post
honestly, your PW drops as your vacuum increases, so much so that the AFRs eventually go really lean before overrun even kicks on.

You can see where overrun kicked on where the PW spiked down to 0 for a split second, that's the only time you weren't injecting fuel.
yeah I can see that but you can see at the same time I'm reading 12 AFR's in the picture right before that happens, do you know why that is?
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Old 06-02-2011, 07:26 PM   #5
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you lifted

the pulse width is at 1.3ms. im sure you idle higher than that. you could try removing more fuel in the map on your 25 and 13kPa rows and see if that helps. but also at the saem respect, the AFR jump way past 15.0:1 before you even cut the fuel completely at the same PW and MAP. So you have some unburned fuel leftover when you close the throttle, the AFR meters it...nothing you can really do about it.
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Old 06-02-2011, 07:55 PM   #6
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yeah wonder if cutting to fuel decel cut will help in that sense, currently its at 2 seconds iirc, maybe 1 second before cut in will help.
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Old 06-02-2011, 08:54 PM   #7
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or increase the "map below"
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Old 06-03-2011, 12:48 AM   #8
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what do you mean by increase the map below?

Do you mean have more points under that point, starting like at 10\14kpa to 20 kpa 30kpa for the load points?
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