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Ungodly amount of fuel just to get it to run poorly.......

  • Thread starter Thread starter Gidgets_95gt
  • Start date Start date Mar 11, 2020
G

Gidgets_95gt

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Feb 18, 2020
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Mar 11, 2020
#1
  • Mar 11, 2020
  • #1
I don't even know where to start to explain. I will just post the tune and logs to start..... It ran fine. Parked the car. When I came back to drive hime it started but immediately died.
 

Attachments

  • 61.0Required.Fuel.msq
    61.0Required.Fuel.msq
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  • 2020-03-11_06.39.12.mlg
    2020-03-11_06.39.12.mlg
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  • 2020-03-11_06.42.02.mlg
    2020-03-11_06.42.02.mlg
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  • 2020-03-11_06.56.33.mlg
    2020-03-11_06.56.33.mlg
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  • 2020-03-11_07.41.04.mlg
    2020-03-11_07.41.04.mlg
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a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
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Mar 11, 2020
#2
  • Mar 11, 2020
  • #2
I will have to take a look at these when i have time, if after the car has been run and it has sat to heat soak and will not start then you need to adjust the ASE, priming, ASE taper.
It is not uncommon for this to happen with the 94-95 mustangs as the IAT is in the airbox and does not normally see the 200* temps the engine bay will reach after it has sat for awhile.
 

Blown88GT

Founding Member
Nov 13, 1999
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Palm Beach Gardens, FL
Mar 11, 2020
#3
  • Mar 11, 2020
  • #3
Probably has nothing to do with tune. I would look at the fuel delivery, i.e., fuel pressure.
BTW, there was no need to start a new thread on the same subject.
 
G

Gidgets_95gt

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Feb 18, 2020
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Mar 11, 2020
#4
  • Mar 11, 2020
  • #4
Thought it was a different subject kinda. Ie different problem than the idle with autotune. Sorry. The original computer doesn't do any better either. I was wondering if it was possible that all my injectors went bad at the same time seeing as I have no idea if they have ever been replaced. I will however check my fuel pressure when I get off work. The fuel pump runs strong and the filter is new.
 

Blown88GT

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Nov 13, 1999
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Palm Beach Gardens, FL
Mar 12, 2020
#5
  • Mar 12, 2020
  • #5
In many cases, what seem like different subjects all have the same root cause.
Fuel delivery could be fuel pump, fuel pressure regulator, injectors.
BTW, maintaining fuel pressure at idle can be strong, but under load can be weak.
 
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Gidgets_95gt

New Member
Feb 18, 2020
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Mar 12, 2020
#6
  • Mar 12, 2020
  • #6
I understand completely. Sorry for making the seperate post. The fuel pump runs but not pushing fuel. Going to drop the tank this weekend and replace the pump with a 255 lph and replace the hoses.
 

Blown88GT

Founding Member
Nov 13, 1999
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Palm Beach Gardens, FL
Mar 13, 2020
#7
  • Mar 13, 2020
  • #7
Just don't resurrect a 10 year old post because it resembles your issue. (LOL)
Reference it, but don't add to it.
Steve is pretty busy with IBEW school, so sometimes I jump in to offer assistance, if it's something I've had experience with.
I have found that some of the replacement pumps don't have an anti-siphon valve. Only one FPR has it, Kirban. Without the anti-siphon valve, hot starts are difficult, resembling a flooded condition.
Remember, the only fuel item that Megasquirt monitors & controls are the injectors.
 
Last edited: Mar 13, 2020
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Gidgets_95gt

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Mar 13, 2020
#8
  • Mar 13, 2020
  • #8
The new pump is installed. Running great. No problem with hot starts so far but we aren't into really warm weather yet either. I have it running and idling pretty good I think. I was kinda curious though. I read something that said the lambda delay table should be changed under the auto tune options. Should it be changed and what is the best way to determine the correct variables for said table?
 

Blown88GT

Founding Member
Nov 13, 1999
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Mar 14, 2020
#9
  • Mar 14, 2020
  • #9
Hot start after 5-10 minute delay. Immediate hot start, no problem.
 
G

Gidgets_95gt

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Mar 22, 2020
#10
  • Mar 22, 2020
  • #10
So I have the car running pretty good in my opinion. The only thing I can not for the life of me figure out is the idle hunting. Seems like nothing I do fixes it. Here is a log and the tune.
 

Attachments

  • HuntingIdle.msq
    HuntingIdle.msq
    119.3 KB · Views: 104
  • 2020-03-22_17.18.45.mlg
    2020-03-22_17.18.45.mlg
    342.7 KB · Views: 146
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