Just picked up a 1993 CA VX (Tons of questions)
 

I just bought a 1993 Honda Civic VX, California model. I have tons of questions so please answer them if you can.

How do I install/wire the 5-wire O2 sensor and FED 49-State VX ECU into my '93 CA VX? Is there a DIY or guide with step by steps and/or pictures?

Should I do the O2 sensor or ECU first? Both at the same time?

Will my car pass CA smog if I have the 5-Wire O2 Sensor & 49-States ECU?

How do I tell the difference between a CA VX ECU and a 49-States ECU? Do they have different part numbers?

Is it possible to install the shift light into my CA VX since they didn't come with one?

What are the ideal compression numbers for a compression test on a VX?

What kind of motor oil should I be using in my VX with 150k+ miles?

Why does my battery light flash on and off while I drive? It doesn't do that while idling. I just replaced the battery too with a brand new Interstate battery just yesterday. Could it possibly be the alternator?

Why is my car idle jumping between about 800 to 1500 under certain loads?
Sometimes it does this, sometimes it doesn't. During a certain time, it didn't do this with my headlights off but with the headlights on, it did. For this, I'm guessing it's the IACV.

Will the ScanGauge II help me in any way? If so, how so?

Welcome to the board!

Most all of your questions have been answered already elsewhere on this forum. A great place to start would be to look into the VX info link in my signature.

And, unfortunately, the SGII will not work in your vehicle.

I suspect that your alternator needs new brushes... you can replace them, pay an alternator shop to replace them, or buy a rebuilt alternator that will have new bearings as well, at higher speeds they bounce around a little and because they are almost gone they don't have as much presure on them.