Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  • Home
  • Questions
  • If I am replacing the engine (D17) for another (D17a2), do I need a computer to match the new engine?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: My car is level in the rear when empty, but when people get in the rear drops down

The rear suspension is low, most likely due to weak rear struts. The struts are gas charged and support the rear end. The struts may be low on gas charge and will not support as much weight as when new...

Q: Engine rebuild or used low mileage engine...? 2004 Ford F150

Hi there - replacing a worn out engine offers several choices: rebuild, replace with a used, lower mileage engine, or install a new or often-called "crate" engine from Ford. In terms of convenience and reliability, a "crate" engine can be...

Q: Can't pass emissions.

The system should be scanned and the 02 sensors checked when the system is enriched to see if the sensors respond correctly. You could just have a defective sensor or a convertor that is bad. Only these tests can determine...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...