Q: If I am replacing the engine (D17) for another (D17a2), do I need a computer to match the new engine?

asked by on August 24, 2016

My transmission is grinding on my 2004 Honda Civic DX. On my look for a new transmission I found a trans and engine together for a good price. The engine I am looking at getting is out of a Honda Civic EX and is a D17a2 compared to my D17. The only difference is in horsepower, torque, and that it has VTEC. Do I need to find a new ECM and/or a new ECU for it to work?

My car has 143000 miles.
My car has a manual transmission.

Hello. Swapping form a non-VTEC to a VTEC engine will require a different computer and wiring harness, as the two engines come equipped with similar, but different engine management systems. These parts are usually not difficult to source as these types of swaps are not uncommon.

Also keep in mind that since both motors are D17 series, it may be possible that the transmission will bolt up directly, without the need to swap the engine. Depending on the circumstances, this could be another cost efficient option to repair the issue.

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