PCM Recalibration required for engine swap?

[DSMOCTANE]

Long story short: My father and I have completely rebuilt a 420a engine and swapped it with the original engine that came with the Eclipse GS. Motor has perfect compression, spark, and timing. When first starting the motor, we had a false DTC code stating that my timing had skipped one or more teeth. Mitsubishi helped me realize that this was due to the ECU being calibrated to the timing marks of the first motor. A dealer blog stated that this false code could be dismissed by resetting the ECU using a DRB-III scanner tool. We had reset the timing variables and that code had disappeared for good. The first two cylinders are running fine, but 3 and 4 show signs of misfiring and the plugs are covered with fuel and oil. MY QUESTION: Since I had to re-calibrate the timing marks using a DRB-III scanner tool at the Chrysler dealership, is there a possibility that more variables within the ECU have to be reset aside from just the timing marks? Has anyone ever done a complete motor swap and experienced issues with the functioning of their ECU with the new motor?

Someone has mentioned to me that often times the pcm needs to be reflashed after an engine swap. Anyone know a bit knowledge more on that or had it done before?

 

[mike420a]

Personally, I've never heard of anyone having to mess with the ECU after swapping the engine, the only reason for it would be if you were swapping your 95/96 engine for a 98/99 or 98/99 for a 95/96, there's a difference on the CAS wires order, and ignition order as well, but haven't heard of messing with the ECU at all.

First you'll have to check the engine timing, forget about the ECU, and check the timing marks with the manual.

I've seen this before, and it mostly ends being about the timing.

Regards