Some confusion about my '89 DX

[Clint]

I am still sorting out my "89 DX. I "assumed" that since it was a carb it had no computer, but yesterday I noticed it has an O2 Sensor in the downpipe below the exhaust manifold. That sent me to PDF manual I have and the O2 sensor is shown but I can not find to what it connects. I thought maybe the Magical Black Box with its numerous vacuum tubes, valves and wires, but did not see it. So to what is the sensor connected?

[Clint]

I would have thought someone would have known this. Mods - if this is in the wrong forum please move it.

[ShyBoyCA6]

it should be a tan or green connection there where it connects. look down on the trans and you'll see it when looking down at it.

[Clint]

The wire is connected - I just want to know if the car has a computer. I have looked at manual online and can not find where it is if there is one. And if the car does not have one, to what is the O2 sensor connected?

[ShyBoyCA6]

The computer is under the driver seat. It is just a small box.

[g.frost]

If not in the main manual, check the '88 manual addendum and look under emissions controls for diagrams/info.

[Clint]

Thanks - I have the 89 Addendum and it IS listed there - I will assume it is considered a OBD1 computer.

[itzdave]

Obd0

[Clint]

Obd0

Huh - I did not realize there was an OBD0 -

[lostforawhile]

it's a no-bd stone age 1 computer, it controls the emissions box and the mixture in the carb , actually it controls a vacuum leak through a special set of valves, fuel is fixed rich, and air is monitored and modified, it's also controlled mechanically but the computer can neither see or control that, and has no idea if there are issues, no on board diagnostics, except the one in the drivers seat

[Clint]

Thanks Lost - That makes sense. It sure makes a Weber look better. If I decide to keep the car I will certainly consider one.