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EGR code 558 95 mustang

  • Thread starter Thread starter Chris530
  • Start date Start date Feb 3, 2023
C

Chris530

New Member
Oct 16, 2022
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1
California
Feb 3, 2023
#1
  • Feb 3, 2023
  • #1
I have a 95 mustang engine and trans in my 63 falcon. I have a egr eliminator installed in it but I have a code 558 for the egr solenoid circuit . This runs to pin 33 on the ECU. Question is what do I need to do with this circuit to trick ECU ?
 

TwoRockTwo

Member
Mar 28, 2021
50
21
18
Rustburg, Virginia
Feb 11, 2023
#2
  • Feb 11, 2023
  • #2
You don’t need to trick the EEC.
If you trick the EEC, it will continue to operate as if the EGR is still there and working properly, and then the EEC will pull fuel & add timing.

Having the CEL on because of an EGR code effectively disables the EGR functions. The EEC knows there is a problem and won’t use it.

If you don’t like the CEL, it can easily be turned off with a tune and the EEC will no longer look for it.

CEL = good
Trick = bad

FYI the EGR lowers combustion chamber temperatures and it’s only active at part throttle, so it doesn’t cost you any power.
 
C

Chris530

New Member
Oct 16, 2022
6
0
1
California
Feb 16, 2023
#3
  • Feb 16, 2023
  • #3
TwoRockTwo said:
You don’t need to trick the EEC.
If you trick the EEC, it will continue to operate as if the EGR is still there and working properly, and then the EEC will pull fuel & add timing.

Having the CEL on because of an EGR code effectively disables the EGR functions. The EEC knows there is a problem and won’t use it.

If you don’t like the CEL, it can easily be turned off with a tune and the EEC will no longer look for it.

CEL = good
Trick = bad

FYI the EGR lowers combustion chamber temperatures and it’s only active at part throttle, so it doesn’t cost you any power.
Click to expand...
Thanks for the info I was under the impression that if I didn’t fool the eec that the egr was there it would not run correctly. What your saying is other than a annoying CEL it is fine. I did pull all codes and that was the only one the I thought would turn light on . Other codes are smog pump related. Etc. question I have a egr delete plugged in where egr is supposed to go but on the egr solenoid circuit I didn’t do anything with pin 33 and that’s what I think is making cel come on. I was thinking if I did something with that circuit the eec would think it was fine and not trigger cel . Your saying leave it be and unhook light or have it tuned off.
 
C

Chris530

New Member
Oct 16, 2022
6
0
1
California
Feb 16, 2023
#4
  • Feb 16, 2023
  • #4
TwoRockTwo
What I was trying to say in last reply is my EGR eliminator is post to trick the ECC into thinking the EGR is properly functioning. But when I did the harness, I didn’t connect pin 33 in the EGR solenoid circuit and I believe that’s why it’s throwing the CEL. I was just wondering where that wire ran so I can hook it back up in hopes it turns light off. I was under the impression the motor would run rich or open loop without the EGR functioning. Thanks.
TwoRockTwo said:
You don’t need to trick the EEC.
If you trick the EEC, it will continue to operate as if the EGR is still there and working properly, and then the EEC will pull fuel & add timing.

Having the CEL on because of an EGR code effectively disables the EGR functions. The EEC knows there is a problem and won’t use it.

If you don’t like the CEL, it can easily be turned off with a tune and the EEC will no longer look for it.

CEL = good
Trick = bad

FYI the EGR lowers combustion chamber temperatures and it’s only active at part throttle, so it doesn’t cost you any power.
Click to expand...
 

TwoRockTwo

Member
Mar 28, 2021
50
21
18
Rustburg, Virginia
Feb 16, 2023
#5
  • Feb 16, 2023
  • #5
No Tricks.

Remove your “eliminator”.
Forget about pin 33.
Let the CEL be on.

You do NOT want the EEC to be using any of the EGR functions/ strategy.
The only ways to accomplish that is by having an EGR fault code (CEL) or having it turned off via a chip tune ($350-$500).

The chip tune will remove the CEL.

The EGR is NOT functioning properly if you delete it or any portion of it. Why would you want to trick the EEC into using those functions/ strategies???
 
C

Chris530

New Member
Oct 16, 2022
6
0
1
California
Feb 16, 2023
#6
  • Feb 16, 2023
  • #6
TwoRockTwo said:
No Tricks.

Remove your “eliminator”.
Forget about pin 33.
Let the CEL be on.

You do NOT want the EEC to be using any of the EGR functions/ strategy.
The only ways to accomplish that is by having an EGR fault code (CEL) or having it turned off via a chip tune ($350-$500).

The chip tune will remove the CEL.

The EGR is NOT functioning properly if you delete it or any portion of it. Why would you want to trick the EEC into using those functions/ strategies???
Click to expand...
Thanks for the info. Only reason I ask about the ECC needing the EGR is that I read on several sites that without the ECC seeing a functioning EGR is will not run properly or run in open loop. I’m not set on tricking the ECC I just want car to run correctly.

Thanks
 

TwoRockTwo

Member
Mar 28, 2021
50
21
18
Rustburg, Virginia
Feb 16, 2023
#7
  • Feb 16, 2023
  • #7
It has nothing to do with open or closed loop.
Whoever wrote that, was completely wrong.

Open loop is for startup and wide open throttle.

The EGR is never active during either of those conditions.
It’s only active at part throttle cruise.
 
C

Chris530

New Member
Oct 16, 2022
6
0
1
California
Feb 17, 2023
#8
  • Feb 17, 2023
  • #8
Gotca other than the CEL leave it be . Thank yoy
 
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