Frostyboost
Probationary Member
- 4
- 0
- May 22, 2013
-
Greenbay,
Wisconsin
91 gvr4- everything was fine until i cut my safc2 out without disconnecting battery.
While it was down, i also changed out my throttle body w/ sensors, alternator, 2g fuel injector harness spliced in, o2 sensor and an EPROM ECU added. The ECU runs my friends car no problem but i go to start mine and notta. So far i have checked the 2 main fusable links for the MPI both are good and no/low resistance with ohm meter. The fuse in the kick panel is good that supplies power to pin 103 at the ECU and power is present there at all times. Pin 102 and 107 on the ECU are not getting any 12v signal at all for some reason when the key is on.
I removed my MPI relay and tested pin 10 on it has a 12v at all times. So i made up a ground for pin 8 of the MPI relay to the body and when i touch it to the ground it works and sends 12v to the ecu at 102 and 107 like it should but i hear the ISC move and normal "key on sounds" for like a split second then it dies off immediately its not holding the power on the pins at the ECU when i connect it and it "boots up".
The check engine light also lights up in conjunction with the sound again only for about 1 second before it shuts off. During that one second i don't hear my fuel pump and since i have my battery relocated to the trunk i ran a hard line from it directly to the fuel pump 12v and tried to start it by having the pump on all time, holding the ground to pin 8 of the MPI relay and turning the key. I get nothing of course, the ECU wont keep power or do anything :/.
Really annoying because it ran fine before i did any of this small work. I tried my OG ECU that ran this same car before the work, nothing. New EPROM, nothing, friends ECU from his 91 tsi awd, nothing. The problem is somewhere in the wires not sure if something is grounded out that shouldn't be or whats going on. Should i try to find or convince my buddy to let me try his MPI relay in my car?
**edit**
Also just checked and the IG1 signal at pin 110 goes hot with key on so the ECU is just not pulling 63 low? This ECU was rebuilt by Terry and has a jumper wire on the bottom side, new caps etc.
While it was down, i also changed out my throttle body w/ sensors, alternator, 2g fuel injector harness spliced in, o2 sensor and an EPROM ECU added. The ECU runs my friends car no problem but i go to start mine and notta. So far i have checked the 2 main fusable links for the MPI both are good and no/low resistance with ohm meter. The fuse in the kick panel is good that supplies power to pin 103 at the ECU and power is present there at all times. Pin 102 and 107 on the ECU are not getting any 12v signal at all for some reason when the key is on.
I removed my MPI relay and tested pin 10 on it has a 12v at all times. So i made up a ground for pin 8 of the MPI relay to the body and when i touch it to the ground it works and sends 12v to the ecu at 102 and 107 like it should but i hear the ISC move and normal "key on sounds" for like a split second then it dies off immediately its not holding the power on the pins at the ECU when i connect it and it "boots up".
The check engine light also lights up in conjunction with the sound again only for about 1 second before it shuts off. During that one second i don't hear my fuel pump and since i have my battery relocated to the trunk i ran a hard line from it directly to the fuel pump 12v and tried to start it by having the pump on all time, holding the ground to pin 8 of the MPI relay and turning the key. I get nothing of course, the ECU wont keep power or do anything :/.
Really annoying because it ran fine before i did any of this small work. I tried my OG ECU that ran this same car before the work, nothing. New EPROM, nothing, friends ECU from his 91 tsi awd, nothing. The problem is somewhere in the wires not sure if something is grounded out that shouldn't be or whats going on. Should i try to find or convince my buddy to let me try his MPI relay in my car?
**edit**
Also just checked and the IG1 signal at pin 110 goes hot with key on so the ECU is just not pulling 63 low? This ECU was rebuilt by Terry and has a jumper wire on the bottom side, new caps etc.
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