'98 Accord LX - P1607 Powertrain Control Module Internal Circuit Malfunction

[JeffKeryk]

I did a front brake job, plugs, oil and other stuff to my friend's 1998 Accord LX 2.3L 4 banger with 141K.
My folks bought this car new and I gave it to my friend, a single Mom, after my they passed. The car was always garaged and serviced.

I notice the check engine light was on, it threw a P1456 Gas Cap and P1607 Powertrain Control Module Internal Circuit Malfunction.
The gas cap needs to be be carefully closed, basically spun around twice. I believe a Honda cap would solve this; they are kinda pricey.

The bigger issue is the P1607; I Googled it and found the PCM may also control the transmission operation; Cindy said it shifted poorly when cold but seems to be OK after a few blocks.
My guess is I need a PCM... Please offer any suggestions as to source and difficulty.
Also, is there any programming involved, such as the starter switch immobilizer?

I appreciate your thoughts. This car should have a lot of life left; I just put axles and rubber on in addition to the other work.
Thanks again.

 

[wpod]

Talk to a Honda shop.

 

[PimTac]

Cindy said it shifted poorly when cold but seems to be OK after a few blocks.

Battery?

 

[The_Eric]

Check/clean battery cables, check/clean all powers and grounds to ecm. Look for loose or corroded pins. Disconnect and load test the ecm power and ground wires with an old head lamp.. If the ecm is receiving good power, then probably a bad ecm

 

[nthach]

It’s hard to kill an ECU unless there’s a power surge/dip taking out the power supply’s components, power is applied to an sensor input/an output is shorted or a bad capacitor.