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Cannot figure out why my engine dies at idle

  • Thread starter Thread starter maisonmays22
  • Start date Start date Apr 25, 2020

maisonmays22

Member
Oct 25, 2019
48
0
6
Amarillo Tx
Apr 25, 2020
#1
  • Apr 25, 2020
  • #1
Engine dies after start up and I cant figure out why.
 

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  • 2020-04-25_20.06.21.mlg
    2020-04-25_20.06.21.mlg
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  • CurrentTune.msq
    CurrentTune.msq
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a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Hillsborough county
Apr 26, 2020
#2
  • Apr 26, 2020
  • #2
well I hate to say this but you have bigger problems than that.. I am going to lay out some of the issues I see from quickly glancing through the tune file, most of these are simply novice mistakes and can be corrected easily.

your final row [value] in the warmup enrichments is set to 125.. this means that even fully warm you are adding 25% of your fuel from this modifier table. This explains the unrealistic values in the VE table.
your req fuel value is half of what it should be, this means you changed something major at some point and did not recalculate or you input the value by hand to compensate for the incorrect warmup enrichment.

as for the car dying on startup, I cannot see what the AFR is because the wideband has not started reading yet. but I will assume based on the condition of the tune it is fuel related.
 

maisonmays22

Member
Oct 25, 2019
48
0
6
Amarillo Tx
Apr 26, 2020
#3
  • Apr 26, 2020
  • #3
went through and made your recommended changes. Now all im getting is surging idle. @a91what
 

Attachments

  • 2020-04-26_12.23.09.mlg
    2020-04-26_12.23.09.mlg
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  • CurrentTune.msq
    CurrentTune.msq
    119.1 KB · Views: 121

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
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Hillsborough county
Apr 26, 2020
#4
  • Apr 26, 2020
  • #4
disable the ego correction.
make the entire area it is surging in one value in the fuel table. the fuel is swinging
lock the timing
do the basic steps first, you made major changes
 

maisonmays22

Member
Oct 25, 2019
48
0
6
Amarillo Tx
Apr 27, 2020
#5
  • Apr 27, 2020
  • #5
Went through and got my idle set better and made a few auto tune runs yesterday. Tell me if this looks better @a91what
 

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  • CurrentTune.msq
    CurrentTune.msq
    119.1 KB · Views: 115

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Hillsborough county
Apr 27, 2020
#6
  • Apr 27, 2020
  • #6
VE table is still very off.. are your injectors the green top 42lbers? if they are your dead time is wrong.

dead time= .743
offset= .121

with your number of squirts set to 4 and the wrong deadtime value you are getting the majority of your fuel from the incorrect deadtime value.

yours 1.3
correct value .743
extra fuel .557 * 2squirts per injector [your settings right now] = 1.114 pw

now this is not that big a deal when the engine is making steam and requires more fuel but at idle this is a lot of fuel.

when you fix this setting the car will be very lean, you may have to double the numbers at idle. once this part is done then we can go back through and work on the parts of the tune that need the most help. It is alot of work but once you have it correct the car will tune much easier.
 

maisonmays22

Member
Oct 25, 2019
48
0
6
Amarillo Tx
Apr 27, 2020
#7
  • Apr 27, 2020
  • #7
TRE-FI-Wide-42LB-8
This is the Part number for the injectors i put in a few weeks ago. I've had a hard time finding all the specs on them but most forums talk about dead times around 1.20. Never have found info on battery correction though.
 

a91what

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10 Year Member
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Apr 27, 2020
#8
  • Apr 27, 2020
  • #8
ah I see, let me try and dig up some information on them
 

maisonmays22

Member
Oct 25, 2019
48
0
6
Amarillo Tx
Apr 28, 2020
#9
  • Apr 28, 2020
  • #9
I think I'm going to get new injectors. I'm not reading anything good about TRE Performance.
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Hillsborough county
Apr 28, 2020
#10
  • Apr 28, 2020
  • #10
I had this same issue with the trickflow injectors.

If you do decide to buy new injectors I suggest deka 60
 

maisonmays22

Member
Oct 25, 2019
48
0
6
Amarillo Tx
Apr 28, 2020
#11
  • Apr 28, 2020
  • #11
Thoughts on these?
 

mustang70

Founding Member
Nov 15, 2001
2,445
2
48
San Diego
Apr 28, 2020
#12
  • Apr 28, 2020
  • #12
If they're legit SD 60lb injectors I'd say you're good. I've tuned with them on a couple different set ups in the past and they worked really well.
 
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