MEGAsquirt A place to collectively sort out this megasquirt gizmo

how to get rid of extra fuel coming off throttle?

Thread Tools
 
Search this Thread
 
Old 06-02-2011 | 01:24 PM
  #1  
Techsalvager's Avatar
Thread Starter
I'm Miserable!
 
Joined: Jun 2009
Posts: 1,866
Total Cats: 0
From: albany, ga
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



Uploaded with ImageShack.us
Attached Files
File Type: msq
CurrentTune.msq (79.1 KB, 118 views)
Old 06-02-2011 | 02:07 PM
  #2  
y8s's Avatar
y8s
DEI liberal femininity
iTrader: (8)
 
Joined: Jun 2005
Posts: 19,338
Total Cats: 574
From: Fake Virginia
Default

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.
Old 06-02-2011 | 02:16 PM
  #3  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 79,819
Total Cats: 4,152
From: Chantilly, VA
Default

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.
Old 06-02-2011 | 07:26 PM
  #4  
Techsalvager's Avatar
Thread Starter
I'm Miserable!
 
Joined: Jun 2009
Posts: 1,866
Total Cats: 0
From: albany, ga
Default

Originally Posted by Braineack
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?
Old 06-02-2011 | 07:26 PM
  #5  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 79,819
Total Cats: 4,152
From: Chantilly, VA
Default

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.
Old 06-02-2011 | 07:55 PM
  #6  
Techsalvager's Avatar
Thread Starter
I'm Miserable!
 
Joined: Jun 2009
Posts: 1,866
Total Cats: 0
From: albany, ga
Default

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.
Old 06-02-2011 | 08:54 PM
  #7  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 79,819
Total Cats: 4,152
From: Chantilly, VA
Default

or increase the "map below"
Old 06-03-2011 | 12:48 AM
  #8  
Techsalvager's Avatar
Thread Starter
I'm Miserable!
 
Joined: Jun 2009
Posts: 1,866
Total Cats: 0
From: albany, ga
Default

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?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
84
04-12-2021 05:21 PM
tazswing
Race Prep
20
10-03-2015 12:04 PM
JxPhan
Meet and Greet
3
10-02-2015 03:17 AM
The Gleas
MEGAsquirt
3
10-01-2015 10:30 AM
lsc224
Miata parts for sale/trade
2
10-01-2015 10:17 AM




All times are GMT -4. The time now is 12:17 PM.