Symptoms:

Video:
When the car starts, it has a nervous idle. The engine is running super lean, I'm getting about 20-25mpg. When accelerating the car sometimes jerks unless it's in a higher gear and at an uncomfortably low RPM (say 1,500 - 1,900).

I included a video of the symptoms and the ECU readout, which I'm pretty sure is saying O2 sensor and intake manifold pressure.

I when I first got the car, I realized that the O2 was out. The ECU readout for this confirmed it so I replaced it. But it never read the O2 sensor was replaced, it simply kept having the same readings.

A friend told me that if the O2 sensor is out for a long time, the ECU/Fuelmap (don't remember the correct term) can sometimes overwork itself and become dysfunctional/broken forever.

Eventually, the problem would go away once the car warmed up. But now, when the car starts, it barley idles over 200 and just cuts off unless I gas it.

What can I do to fix this or help triangulate the problem better?

Thanks people of Honda-Tech!

 

The ECU ignores O2 sensor inputs until the engine is fully warmed up.

Any CEL codes? If so, post them.

Have you done a full ignition system tune up?

 

I tried recording the light codes in the video. It appears to beep once (o2 sensor) then 8 times (intake manifold pressure).

No I haven't tuned the ignition. Bought the car for $1100, pretty much been keeping maintenance minimal for the past 3 years. What does an ignition tune up entail?

Thanks. I'll let it get warmed up fully and try driving.

 

I saw codes 1, 8, and 14.

If you reset the ECU, do all three codes return?

Code 8 is actually a problem in a distributor sensor circuit. Code 14 is an idle system issue.

Full ignition system tune up = plugs, wires, cap, rotor, ignition timing.

 

The codes I'm going off are coming out of the Wagon's manual, but I might be remembering wrong. And no, the only thing I've replaced on the car since I've had it for three years were the plugs, so that is definitely overdue.

From my understanding, if one were to reset the ECU, it is simply just disconnecting the battery for a duration of time (I've always heard random times with Hondas -- 30 secs, 10 minutes, etc), am I correct?

It's a 1991 Wagon DX if this helps. Should have mentioned that in the title.