On 3 Aug 2018 18:52:56 GMT, Scott Dorsey wrote:

Right. The error message you got about the sensor was ALSO unrelated to
the sensor. The error message says the output of the sensor is out of
range. It's out of range because the engine is running way too rich
or way too lean.

Understood. The error is just an error in the input, output, or power of
the sensor.

The OBDII tester gives us a 800 rpm reading at idle. Dunno how to increase
the idle speed yet, as this car isn't mine (mine is a bimmer which is a
drive by wire mechanism).

You don't. You find the vacuum leak or the bad idle control valve or
whatever it is that is causing the mixture to be all wrong, and then
your idle speed will stabilize and you will be able to accelerate again.

Always wanted to buy a good smoke tester at a good price that a home
mechanic can make an argument for on cost/benefit analysis.