how to get rid of extra fuel coming off throttle? - Miata Turbo Forum - Boost cars, acquire cats.

Go Back  Miata Turbo Forum - Boost cars, acquire cats. > Performance & Tuning > ECUs and Tuning > MEGAsquirt
Reload this Page >

how to get rid of extra fuel coming off throttle?

MEGAsquirt A place to collectively sort out this megasquirt gizmo

how to get rid of extra fuel coming off throttle?

Old 06-02-2011, 01:24 PM
  #1  
I'm Miserable!
Thread Starter
 
Join Date: Jun 2009
Location: albany, ga
Posts: 1,866
Total Cats: 3
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, 77 views)
Techsalvager is offline  
Old 06-02-2011, 02:07 PM
  #2  
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,119
Total Cats: 477
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.
y8s is offline  
Old 06-02-2011, 02:16 PM
  #3  
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 75,089
Total Cats: 2,114
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.
Braineack is offline  
Old 06-02-2011, 07:26 PM
  #4  
I'm Miserable!
Thread Starter
 
Join Date: Jun 2009
Location: albany, ga
Posts: 1,866
Total Cats: 3
Default

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?
Techsalvager is offline  
Old 06-02-2011, 07:26 PM
  #5  
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 75,089
Total Cats: 2,114
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.
Braineack is offline  
Old 06-02-2011, 07:55 PM
  #6  
I'm Miserable!
Thread Starter
 
Join Date: Jun 2009
Location: albany, ga
Posts: 1,866
Total Cats: 3
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.
Techsalvager is offline  
Old 06-02-2011, 08:54 PM
  #7  
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 75,089
Total Cats: 2,114
Default

or increase the "map below"
Braineack is offline  
Old 06-03-2011, 12:48 AM
  #8  
I'm Miserable!
Thread Starter
 
Join Date: Jun 2009
Location: albany, ga
Posts: 1,866
Total Cats: 3
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?
Techsalvager is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Full_Tilt_Boogie
Build Threads
63
08-09-2018 07:54 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


Quick Reply: how to get rid of extra fuel coming off throttle?


Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2018 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.