I am working on my stepson's 91 civic dx and got a code 1, O2 content. So i replaced it with a bosch universal O2 sensor and it still runs the same as before. It is real boggy until you get to 37mph, then it goes like hell!!! Once in awhile it will shoot code1 again. Anyone have any ideas what would cause this? Every time you get to 37mph on the nose the problem stops, trying to get there is a b!#@h! Any help would be greatly appreciated. Tim

 

Bumpity

 

I had similar issue with 93 Accord. It run really bad until the engine hit 4000rpm. Long story short, it had brand new Bosch O2 sensor with proper plug hooked up from the factory, bought from a local parts store. I replaced it with NGK O2 sensor and the problem went away and never come back since.

If I were you, I would double check the wiring on the sensor as well as the system side. And, then if it (wires) was looking good, I may change it out to NGK sensor.

You could Goggle for online sellers for it if it was not available from your local stores. That is what I had to do.

The local store had accepted my return of Bosch sensor, which was nice, I thought. It was black with heavy soot deposit,,,,,

 

Check the fuel pressure. Make sure the vacuum hose on the fuel pressure regulator is hooked up properly. Does it put out black smoke like running real rich?

Misfiring due to weak sparks is often worse at low rpm. Also check the timing.

 

Misfiring due to weak ignition system can be aggravated by increasing of intake manifold pressure, such as going up hill or accelerating. It can happen in any gear or any vehicle speed. If it was due to really weak/bad spark plug wires, you could see it happening as faint sparks in the engine compartment in the dark with engine idling.

Good luck with your car,,,,