Replace W124 1988 - Engine W104 3.2L petrol.

[Mistral]

Greetings to all,

I am undertaking an engine replacement project on my 1988 W124. I have added a 3.2L M104 petrol engine from a 1997 S-Class, which was originally equipped with an automatic gearbox. I installed the engine together with its ECU, the original wire harness (engine harness connected to connectors E and F of the ME2.0 ECU), and incorporated the DAS, baggage compartment, and key utilising this wiring diagram:
Explanation of Pin Functions

A2 +12V subsequent to ignition (KL15) Power supply for the ECU through the ignition relay
B4 +12V battery (KL30) Permanent electrical supply (fuse)
Grounding of A3, A7, and A8 oecus
C40 BEGIN Signal initiation input
D14 Park/Neutral Validation of automatic gearbox (must be energised to permit ignition)
C29 Fuel Pump Relay ECU output regulates the fuel pump with a relay.
F6 Coils Cylinder 3/4 Ignition Control for Cylinders 3 and 4
F13 Coils Cyl 2/5 Ignition control for cylinders two and five
F20 Coils Cylinder 1/6 Ignition regulation for cylinders 1 and 6
E1, E2, E13, E14, E12n5je, and E12e6urs ECU provide grounding for the injectors, which share a common +12V supply.
Crankshaft Position Sensor (CKP) for E37/E38 Crankshaft
Camshaft Position Sensor (CAM) for E39/E40 Camshaft Position Signal
E47 Mass Air Flow Meter
E45 IAT - Intake Air Temperature
E29 CLT Coolant Temperature
Formula 1/Formula 2 Electronic Throttle Body (ETB) Electronic Throttle Regulation
Throttle Position Sensor (TPS) for E31/E32/E33/E34 Throttle Position Sensors
D7/D8 O2 Bank A Oxygen Sensor Signal and Ground
C31/C32 O2 Bank B Oxygen Sensor Signal and Ground
A5/B1 O2 Heater Supply for Lambda Sensors

I successfully created the OBD port, enabling me to read error codes. I substituted the automated flywheel with a manual variant (60-2). However, I have been unable to initiate the engine thus far. I am encountering trouble code P0341.

Upon further investigation, I discovered multiple discussions referencing a grounding issue. I have re-established all the ground connections; yet, the issue continues to remain. I have chosen to compose this message to solicit assistance. Does anyone possess any thoughts or recommendations for addressing this issue?

Thank you in advance.

[CyberNinja]

Doesn't the W210 possess a formidable security system? The removal of the ignition switch and module remains ambiguous.

[Mistral]

Thank you for your response. I have removed the antenna (bag) situated near the ignition switch, as well as the chip and the DAS module located behind the dashboard of the W140. Initially, I saw a "FAULT DAS" message; but, upon locating the precise DAS diagram, the issue vanished, enabling me to access and interpret engine trouble codes such as P0431.

[CyberNinja]

That is the extent of my input; I believe you may need to operate a standalone ECU. Although it may be overly opaque, there are individuals proficient in SDS who could assist with coding. Best of luck; it appears to be an enjoyable transformation once initiated.

[Mistral]

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