Hi, I have a '90 Si, and my CEL comes on every time after driving for a while (30 minutes)
The ECU short blinks once, so I replaced the O2 sensor; however, it still comes on as before.
The distributor, spark plugs, and spark plug wires were also recently replaced; the alternator, however, is making noice.
Please advice, thanks very much.

Symptoms:
When the CEL comes on, it feels like the car is choking (it shakes, and it accelerates a lot slower) The RPM needle moves up so slow even when I gas hard. It's as if it lacks of air or fuel.

 

Anyone?

 

if you replaced the o2sensor then you could have a short or loose conection.

 

Did you get an o2 with a plug or did you have to add your old plug. o2 wiring needs to be soldered not butt connected.

 

o2 just like everyone said. check connections, reset ECU, if problem continues buy an o2 install call it a day.

 

I bought a new o2 with a plug, and I just plugged it in. It only has 1 wire.
Could a bad fuel injector, or even a bad idle controller that's causing this?

 

i think a code 1 is a bad ecu try another ecu in your car and see if the codes stops

 

I thought code 0 is bad ECU... According to https://honda-tech.com/zerothread?id=468260 , code 1 is o2 sensor?

 

Yes code 1 is o2. Clear the ecu disconnect the battery for 20 seconds and see when the light comes on.

 

I've already done that 3 times, and the CEL still comes on after 15 - 30 minutes of driving.

 

what brand o2 did you buy? a crappy one might be giving you problems.

i believe bosch is closest to oem you can get without shellin out the mad cash

 

I bought a regular aftermarket o2 sensor... Any chances that other things could have caused this? I think that I have a bad injector or idle controller because my idle is not stable either.

 

it's prob not too far fetched

maybe try this first:

https://honda-tech.com/zerothread?id=699787

 

That fixed my unstable idle problem. Thanks.
However, I still get code 1; I even replaced another new o2 sensor. What else can cause code 1? I'm pretty sure that the o2 & the ECU are good as well as the connection...