I have a replacement out of another '99 non-turbo. Does it matter whether the donor car was automatic or 5 speed, and are there additional issues with an ECM swap? Thanks.

 

Usually on the 99 and up cars the ECU is specific to the car only.
You cant just swap them out.

 

Thanks tech. Do you think even if I got an ECU from a same model year, same engine, same transmission V70 I would still be unable to install a used ECU? It seems hardly worth it to pay the cost of a brand new ECU for a 200k mile car. Any alternatives to a new ECU you can think of?

I have a front O2 sensor always reading a flat 0.5 volts in my OBDII scanning software regardless of what sensor I connect to it. The rear O2 sensor works normally and I get a real reading from it. And when there's nothing connected to the harness for the rear sensor it reads 0 volts. So something is really screwy with the wiring or the ECU ports for my front O2 sensor. This electronic crap is really a shame given the car is in pretty good mechanical shape for 200k miles.

 

The 1999 cars are networked cars.
The Vin# is programmed into the car. Which means you can't just throw any computer in there.
I have never tried so I can't tell you 100% if it will work or not.
Another option might be to try to have a aftermarket tune done to the computer and see if it fixes the problem.