I have a weird Problem with my car:

I previously used the 90550001 software on my Evo 7/8 MR ECU which worked fine so far.
Because i'm going to change fuel pump and injectors soon for E85 i wanted to use the 96260009 tephra v7 software. First thing i've encountered: The Evo8 software seems to check the second fuel pump relay thet shortcuts the resistor. As i don't have this installed in my Galant but the old ECI-Relay, i just wired up an relay to pin 39 so the check is positive.
With this installed, the car starts up fine, but only right after i turned the key - if i wait a few seconds, it wont and i get DTCs for fuel pump relay, atmospheric pressure sensor (which is OK as it's not yet wired to the ECU) and EGR sensor (not installed -> OK) plus knock sensor (don't know why - i have an evo 8 sensor installed and it worked woth 90550001).

If i turn the key immideately from off to start, it starts perfectly and runs smoothly at 1000rpm (a bit rich, but nothing to bother now). but after ~3-5sec it just stalls and i get DTCs Barometric pressure sensor, Injector circuit, Fuel pump relay, Ignition coil, Ignition circuit

the injector circuit error seems to come from disabling closed loop via periphery bit as i got thet DTC also on 90550001 when driving full-time open loop.
igbition circuit comes from the missing tacho signal input as i'm using the old ignition transistor which has an inverted signal compared to the evo transistor packs. so that error is "normal" for my car.

the other errors don't make any sense to me, as the pinout is just the same for evo 7 to 8 for these sensors. It seems like the ECU is killing the ECI relay after a while, shutting down sensor and injector/ignition power supply, causing these errors and the engine to stall.

But i'm completely stuck on why the software is switching the relay off (i can hear the click right when the engine dies) - immobilizer? valet mode? but both are disabled...


Maybe someone had encountered a similar problem and can give me a hint?

the cur runs perfectly with 90550001, so i don't think the problem is engine/wiring-related unless there is something the evo8 software checks which the evo 7 software doesn't... (resistance, current...)


edit:
I just remembered an old 1.3l colt/mirage (no MAF, only IAT/MAP sensors) with a similar problem when the MAP sensor was plugged off - i will check this tomorrow or monday...

 

96260009 is for a 3 plug ecu with totally different pinout use v7 for 90550001

 

As the car does the same thing on 96530006 ROM and 9653 and 9626 are interchangable i think it's related to some initial check the evo 7 software (9055) doesn't have implemented or when giving negative result doesn't cause the engine to stop but with the evo 8 software does...

I also found pin 40 is used as additional GND for sensors on the VIII - I'll connect it to pin 92 (sensor ground for evo 7) and see if it helps.

To double-check i've started to make an adaptor harness for one of the 3-plug ECUs i have here.

 

9653 is interchangeable but you need to adjust the HEX imobiliser setting. Much easier to use V7 9055 as Todd says.

 

I would guess the ECU is driving the fuel pump rely via the HI-Speed relay circuit, which has a timeout after starting - thus the engine quits.

Do as Todd and Burgers suggest and use 9055, either v5 or v7.

 

use a V7 version of 90550001, I used it on 2 cars, runs fine.