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Injector dead times

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Old May 15, 2021 | 04:42 PM
  #1  
denElias's Avatar
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Default Injector dead times

Hi guys,

What is the difference between the 2 dead times listed below?
I can't seem to find any information about this.

Currenty I have a problem that my injectors deliver too much fuel at idle.
I used the correct dead times from the website for my ev4 640cc injectors.
I have a 1990 1.6 engine





Kind regards,
Old May 15, 2021 | 05:14 PM
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MS3x has 10 total injector drivers across two different styles, two (1 and 2) on the old as **** re-retrofit three times base PCB, and 8 more (A-H) on the MS3x card. Hence, MS3x injector channels and mainboard injector channels.

If you are not using bank 1/2 then the settings on the lower half aren't going to do anything.


Old May 15, 2021 | 05:59 PM
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What fuel pump are you using?

Did you retune VE with the new injectors?

Attach your current tune and a log.
Old May 16, 2021 | 04:15 AM
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Stock fuel pump.
Injector don't leak, tested that.
Fuel table retuned, it runs fine when not idling.

Attached Files
File Type: mlg
idle.mlg (116.6 KB, 42 views)
File Type: msq
newInjectors.msq (263.2 KB, 48 views)
Old May 16, 2021 | 12:54 PM
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That's not a tuned VE table. Try again.

I don't see anything that would indicate a deadtime issue. You just need to tune VE properly.
Old May 16, 2021 | 01:09 PM
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I already spent a lot of time trying to get the fuel correct.
When you set all cells between 0 and 30 kpa to a fixed number, the car should idle fine around 14 afr right?
I can’t get this to work, above 12 afr it starts hunting like crazy
Old May 16, 2021 | 01:20 PM
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Originally Posted by denElias
When you set all cells between 0 and 30 kpa to a fixed number, the car should idle fine around 14 afr right?
Did you read that somewhere? Your fueling requirements at 30kpa are different than they are at 10kpa. Hunting is what I would expect if someone did that. What your current tune is showing is even worse though. You have a giant step from 24-30kpa.

This is not a properly tuned VE table.



Old May 16, 2021 | 02:05 PM
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There is nothing wrong with fixing 10-30kpa values from 800-1200rpm for an easy start. He isn't going to idle at 10kpa anyways. I do the same and it is ROCK SOLID.
Ego is off, DFCO is on, but only active >8000rpm That shouldn't be a problem...

It really seems like a VE problem like Spartan said
Old May 16, 2021 | 02:42 PM
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Haha yes was fcking around with fuel cut too, made sure it would not interfere

I will try adjusting fuel some more, but i’m afraid it won’t solve my problem.

It idles rock solid at 12 afr, maybe I should just leave it that way?
Old May 16, 2021 | 03:32 PM
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The log you uploaded doesn't look rock solid, its oscillating pretty bad even when at 12 AFR

Transitions between VE Cells should be much closer together. Tune needs lots of work in general.

Only way you would need to idle at 12 AFR is with some shitty injectors running batch injection. You have good EV14 injectors and a good ECU running semi-sequential injection
Old May 17, 2021 | 05:23 AM
  #11  
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So what I did test is set all values in an area to a fixed value (fuel and spark)
When I set them to 68, idle is very stable at 12 afr.
When i start lowering all fuel cells to like 65, it starts hunting...

Can maybe a vacuum leak be the cause of these problems then?
Can a vacuum leak even be possible when map is around 28?



Old May 17, 2021 | 05:30 AM
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Possible. I had idle vac around 28-30kpa when one rubber plug on the intake manifold popped off, so not a big difference to normal idle vac. Noticed revs came down way slower than usual und idle startet hunting badly most of the time.
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