all black 4G63
Proven Member
- 254
- 43
- Aug 5, 2019
-
Chicago,
Illinois
Would like to know if it will cause any damage to the ECU if the MPI relay is eliminated and switched B+ is ran to pin 107 (C-59) of the ECM?
I would also be eliminating all factory fuel pump control circuits (pins 56, 13, and 108 at the ECM) as I would run a HP pump on a separate replay and switch?
I am assuming pin 108 (C-59) is used as a crank sense to enable fuel pump control after the key is rotated from start to run and an RPM signal is obtained? I assuming the ECM does this by applying ground to pin 56 (C-60) after the key is rotated from "start" to "run"?
I am also assuming the ECM applies ground to pin 63 (C-60) to close the MPI relay contacts when IGN B+ is applied to pin 110 (C-59) when the key is switch to KOEO?
I have attached a photo of the MPI Circuit out of the 1992 Laser/Talon Electrical service manual. I am working with a 1992 TSI manual AWD
Thank you for your input and assistance.
I would also be eliminating all factory fuel pump control circuits (pins 56, 13, and 108 at the ECM) as I would run a HP pump on a separate replay and switch?
I am assuming pin 108 (C-59) is used as a crank sense to enable fuel pump control after the key is rotated from start to run and an RPM signal is obtained? I assuming the ECM does this by applying ground to pin 56 (C-60) after the key is rotated from "start" to "run"?
I am also assuming the ECM applies ground to pin 63 (C-60) to close the MPI relay contacts when IGN B+ is applied to pin 110 (C-59) when the key is switch to KOEO?
I have attached a photo of the MPI Circuit out of the 1992 Laser/Talon Electrical service manual. I am working with a 1992 TSI manual AWD
Thank you for your input and assistance.