4G63 SOHC Non Turbo in a Galant EA5A Chassis

[madhouse12]

Hi. First post here and its a complicated one. I have searched the forum and have not found anything on this topic so here goes.

I have a 2004 Galant VR 4 speed automatic that originally came with 6A13 engine (not the twin turbo variant). The previous owner blew up the engine and replaced it with a 4G63 SOHC non turbo engine.

I recently opened part of the dashboard and saw that there are many unconnected connectors. There is a MAP sensor just lying on the passenger side foot well and there is a hole on that side as well. Post catalytic convertor O2 (I am not sure if there should be one or not) is also missing.

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In the engine bay I tried to cross match the MAF sensor (the model number on it is long gone) with other online and it seems to me that it is from a 6A13 engine as they came with a 5 pin connectors and 4G63 ones usually have a 7 pin connector.

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Basically, if you excuse my language, the car is a bastardized version of itself and I am trying to fix it. Can you check the pictures and make any sense of it because I am a newbie at this stuff and can't seem to find the right info anywhere. The only errors OBD is throwing is P0136 (O2 Sensor circuit malfunction Bank 1 Sensor 2) and P0141 (O2 Sensor Heater circuit Bank 1 Sensor 2).

Thanks

 

[steve]

The Eighth gen Galant is a bit outside the wheelhouse for a DSM forum but we try to help people even when they are strays.

Have you tracked down the Factory Service Manuals for this year Galant? You'll need both the electrical diagrams for the original 6A13 as well as for the replacement 4G63. (was the 4G63 a DOHC or SOHC version in the 2004? I can't tell what would have been there.)

On most 4G63's from that timeframe would have a second O2 sensor post-catalytic converter in the exhaust.

I have to assume that the ECU was also swapped since a 6A13 ECU isn't likely to work with a DOHC 4G63.

 

[madhouse12]

The Eighth gen Galant is a bit outside the wheelhouse for a DSM forum but we try to help people even when they are strays.

Have you tracked down the Factory Service Manuals for this year Galant? You'll need both the electrical diagrams for the original 6A13 as well as for the replacement 4G63. (was the 4G63 a DOHC or SOHC version in the 2004? I can't tell what would have been there.)

On most 4G63's from that timeframe would have a second O2 sensor post-catalytic converter in the exhaust.

I have to assume that the ECU was also swapped since a 6A13 ECU isn't likely to work with a DOHC 4G63.

Hey!. Finally a saviour...
I am sorry for posting it in this forum but I was getting nowhere on others. Since the engine swapped belongs to old gens of the car so I thought you guys might be able to help.

From what I have gathered so far, the engine wiring belongs to the original 6a13 and they have managed to make it work somehow with 4g63 SOHC. I think this because there are many unconnected connected inside the cabin that are on the main engine wiring loom.