MEGAsquirt A place to collectively sort out this megasquirt gizmo

Engine stall after throttle lift

Thread Tools
 
Search this Thread
 
Old 10-23-2018, 05:34 PM
  #1  
Junior Member
Thread Starter
 
Vincentmiata's Avatar
 
Join Date: Mar 2011
Location: Eindhoven, The netherlands
Posts: 197
Total Cats: 19
Default Engine stall after throttle lift

So i got the car back running after 1.5 years, but with no turbo at the moment. My idle hunting is almost gone, just little hunting now, but my biggest problem is now when i lift the throttle after revving the engine stalls. Always. The idle valve does not do anything. If i let go throttle slowly and let the RPM drop slowly there is no problem


Is this because of those engine state settings? Like decelerating slowly or fast. I never looked at those settings because i tought they were only for dataloggging etc.


ive added a small datalog of one stall. The other ones are the same


EDIT: Biggest changes are electric waterpump and an electric hydraulic powersteering pump, but those thing should not be a problem.
Attached Files
File Type: msl
2018-10-21_17_modified.msl (54.0 KB, 84 views)
Vincentmiata is offline  
Old 10-23-2018, 05:43 PM
  #2  
Junior Member
 
dglb99's Avatar
 
Join Date: Feb 2017
Location: Portland Oregon
Posts: 78
Total Cats: 2
Default

Looks to me like you aren't getting enough fuel, AFR readings show 18.6 from 2100 RPM until it stalls.
dglb99 is offline  
Old 10-23-2018, 06:00 PM
  #3  
Junior Member
Thread Starter
 
Vincentmiata's Avatar
 
Join Date: Mar 2011
Location: Eindhoven, The netherlands
Posts: 197
Total Cats: 19
Default

Could be. But the idle valve stays also at minimum duty. Shouldnt that be the one that 'catch' the rpm?
Vincentmiata is offline  
Old 10-23-2018, 06:07 PM
  #4  
Junior Member
 
dglb99's Avatar
 
Join Date: Feb 2017
Location: Portland Oregon
Posts: 78
Total Cats: 2
Default

Could you post your tune or your idle settings? You are correct, the idle valve should open to help catch the engine as it slows down. With that said, for some reason, the data log also shows it running completely lean.
dglb99 is offline  
Old 10-23-2018, 06:14 PM
  #5  
Junior Member
Thread Starter
 
Vincentmiata's Avatar
 
Join Date: Mar 2011
Location: Eindhoven, The netherlands
Posts: 197
Total Cats: 19
Default

Here is the currenttune

Some things are maybe way of i was only trying to pass inspection and could not drive it yet

i did drive thousand of kilometers with almost the same tune. And never had a problem like this if i remember correctly. Its a long time ago
Attached Files
File Type: msq
CurrentTune.msq (261.4 KB, 80 views)
Vincentmiata is offline  
Old 10-23-2018, 06:50 PM
  #6  
Junior Member
 
dglb99's Avatar
 
Join Date: Feb 2017
Location: Portland Oregon
Posts: 78
Total Cats: 2
Default

Ok, I have a few ideas you could try. In your closed loop idle settings, I'd try making this change to the shift settings.
For this number of seconds:(s) I have a feeling your idle valve wasn't opening was because you were got above 2,000 rpm the ecu is now going to wait 2 seconds until it can open the idle valve again. Try setting this to 1 second or even less, maybe half a second. For reference, I looked at my tune, and I currently have that set to 0.1 seconds.

Hopefully, that will get your idle valve to open up sooner and catch the engine as it slows down. Your initial idle values look fine to me. I am not sure why it went really lean in the log you uploaded. It looks like you have wall wetting acceleration enrichment turned on. I would turn all of your acceleration enrichment off for now until you figure out why it is going lean on deceleration.

You can also play around with idle spark advance settings. You can set it up so that if your engine dips below target idle speed it will add a little timing to help catch it from stalling and raise the rpm again.
Hopefully, this gives you some ideas to try.
dglb99 is offline  
Old 10-23-2018, 06:54 PM
  #7  
Junior Member
Thread Starter
 
Vincentmiata's Avatar
 
Join Date: Mar 2011
Location: Eindhoven, The netherlands
Posts: 197
Total Cats: 19
Default

Thats a good idea about the number of seconds. Thats why it didnt stall on the drive to inspection. On a drive it is longer than 2 seconds. But only revving it for like 0.5 sec it has to wait 1.5 sec more to kick in.

good idea thx for that. Ill try it tommorow when im at the car
Vincentmiata is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Tominos
MEGAsquirt
8
06-04-2015 04:36 AM
elior77
MEGAsquirt
15
11-05-2014 03:06 AM
miatadaxdriver
MEGAsquirt
5
03-29-2014 09:09 PM
asellus
Hydra
9
06-09-2012 12:30 AM
ZX-Tex
Adaptronic
66
09-14-2010 10:01 PM



Quick Reply: Engine stall after throttle lift



All times are GMT -4. The time now is 03:27 PM.