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94 Mustang GT, wont idle after bigger injectors.

  • Thread starter Thread starter LZSN95
  • Start date Start date Apr 17, 2018
L

LZSN95

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Apr 17, 2018
#1
  • Apr 17, 2018
  • #1
I installed bigger injectors (24#) now it wont idle. I think it's taking timing out when it senses the extra fuel and making it stall. That's my guess so far. Does this sound right to anyone?
I didn't get a calibrated MAF for the 24s because I'm switching to Megasquirt.
 
Last edited: Apr 17, 2018

a91what

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#2
  • Apr 17, 2018
  • #2
It wont idle because it still thinks it has 19lb injectors. You have about 25% to much fuel and the car can't remove anymore based on minimum pw settings.

I am the resident MS guy see my sig for the megasquirt help and tech threads.

You may want to do some serious reading on how efi works before trying to tackle a standalone efi system. A rudimentary understanding is necessary.

I suggest you look into the ms2/extra documents and read the beginners guide.
 
L

LZSN95

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Apr 8, 2018
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Apr 17, 2018
#3
  • Apr 17, 2018
  • #3
a91what said:
It wont idle because it still thinks it has 19lb injectors. You have about 25% to much fuel and the car can't remove anymore based on minimum pw settings.

I am the resident MS guy see my sig for the megasquirt help and tech threads.

You may want to do some serious reading on how efi works before trying to tackle a standalone efi system. A rudimentary understanding is necessary.

I suggest you look into the ms2/extra documents and read the beginners guide.
Click to expand...
Could you send me a link for the beginners guide. I was pretty sure I was going to have some issues without getting a tune. I didn't think it would be that bad though Haha.
 

a91what

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#4
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LZSN95 said:
Could you send me a link for the beginners guide. I was pretty sure I was going to have some issues without getting a tune. I didn't think it would be that bad though Haha.
Click to expand...
Sure, the guide is MS specific however.

If you look in the classifieds on this site I believe fastdriver is selling a maf for 24lb injectors ar a good price.
 

jozsefsz

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#5
  • Apr 17, 2018
  • #5
If you don't have the megasquirt yet, and don't have the calibrated MAF, you can effectively turn your 24's back into 19's by reducing fuel pressure with an adjustable fuel pressure regulator and get the car to run ok. If it's all just temporary...
 
L

LZSN95

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Apr 18, 2018
#6
  • Apr 18, 2018
  • #6
a91what said:
Sure, the guide is MS specific however.

If you look in the classifieds on this site I believe fastdriver is selling a maf for 24lb injectors ar a good price.
Click to expand...
Thanks for the heads up. I was trying to avoid buying a maf for 24lb injectors since I went need it with the megasquirt.
 
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LZSN95

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#7
  • Apr 18, 2018
  • #7
jozsefsz said:
If you don't have the megasquirt yet, and don't have the calibrated MAF, you can effectively turn your 24's back into 19's by reducing fuel pressure with an adjustable fuel pressure regulator and get the car to run ok. If it's all just temporary...
Click to expand...
I could give that a try for now just to see. What should the fuel pressure lowered to?
 

a91what

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#8
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I'm not a fan of the fuel pressure method as it affects the injector pw breakpoints but in this case it should work just fine.

Based on the rc injection calculator you need to set your pressure at 28psi vacuum removed.
That's pretty low.
 
L

LZSN95

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#9
  • Apr 18, 2018
  • #9
a91what said:
I'm not a fan of the fuel pressure method as it affects the injector pw breakpoints but in this case it should work just fine.

Based on the rc injection calculator you need to set your pressure at 28psi vacuum removed.
That's pretty low.
Click to expand...
I was thinking it may damage the injectors. I'll eather switch back to th19lb injectors for the meantime or just buy the new ECU.
 

a91what

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#10
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I would do that.

here are the manuals
http://www.msextra.com/manuals/ms2manuals/
 

a91what

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#11
  • Apr 18, 2018
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also what MS varient are you planning on buying?? if it is a plug and play style i suggest going with the stinger pimp.
 
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LZSN95

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#12
  • Apr 18, 2018
  • #12
a91what said:
I would do that.

here are the manuals
http://www.msextra.com/manuals/ms2manuals/
Click to expand...
Switch back or buy the ECU?
 
L

LZSN95

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#13
  • Apr 18, 2018
  • #13
a91what said:
also what MS varient are you planning on buying?? if it is a plug and play style i suggest going with the stinger pimp.
Click to expand...
Yes it's PIMPxs. I was just saying megasquirt as a general term. I know some people like one more than the other. I've been talking with those guys and they are very responsive and helpful. Not that others arent, I've only talked to the guys at Stinger. Very helpful though.
 

a91what

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All of them are helpful however the Stinger Pimp XS is just a superior system IMHO, i dont even own one nor have i bought a product from them before. I have however helped tune quite a few of them, If i were you i would do whatever they suggest to go full sequential. Overall you will be much happier with the drivability.
 
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LZSN95

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#15
  • Apr 18, 2018
  • #15
a91what said:
All of them are helpful however the Stinger Pimp XS is just a superior system IMHO, i dont even own one nor have i bought a product from them before. I have however helped tune quite a few of them, If i were you i would do whatever they suggest to go full sequential. Overall you will be much happier with the drivability.
Click to expand...
Ain't nothing to it but to do it at this point. I'm just a little nervous
 

a91what

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#16
  • Apr 18, 2018
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Dont worry, i happen to know someone who can help
 
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LZSN95

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#17
  • Apr 18, 2018
  • #17
a91what said:
Dont worry, i happen to know someone who can help
Click to expand...
I'm assuming you mean yourself. Haha
 

a91what

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#18
  • Apr 18, 2018
  • #18
maybe.
 
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