I think O2 sensor is going......

[CIVICDXDUDE]

Hello....newb civic owner here....I just picked up a 1998 Honda Civic DX with 176000 km on it. Everything runs great but I noticed the occasional "surging" when I'm trying to accelerate while the engine is cold. I know that the fuel pump was recently replaced prior to me purchasing the car so I'm thinking it may be an O2 sensor causing this problem.

The best way I can describe the problem is that as I am attempting to accelerate soon after I turn on the engine (especially accelerate hard) the engine occasionally loses power and the car surges as I keep holding down the gas pedal. Once the engine is warmed up the problem goes away.

I've looked at forums and I think it may be bad O2 sensors.

1 I know that there are two sensors (one on top of the catalytic converter just below the exhaust manifold and the second at the bottom of the catalytic converter) if I were to replace them do I order two of the same sensors or are there different models (one upper and one lower)?

2. Is there anything I can do or check to rule out another possible issue before I order another set of O2 sensors?

Thanks

 

[xxBLOOD88SHOTxx]

You could stop beating on your car when it's cold.

 

[XpL0d3r]

I don't think it's the o2 sensors. When the car is first started it runs open-loop, meaning that until it reaches operating temp, it's A/F ratio is based solely on the ECU without any feedback from the sensors.

If you had a bad o2 sensor, your issue would be reversed; the car would run great cold, and would slack once warmed up.

Does the engine struggle at a specific RPM? Do you have a CEL on?

Also, off topic, you're in Kingston, ON? I sometimes get Tinder matches from up there when I'm in Watertown, NY

 

[CIVICDXDUDE]

Hey Guys,

I don't think I'm overdoing it when its cold. By accelerating hard I'm speaking about getting it up to traffic speed within 20 seconds from my drive way. I've heard that O2's control the fuel / air ratio and when they are faulty the engine reverts to a "safe" setting that could mean loss of power.

CEL is not on, engine does not struggle to maintain RPMs. Engine runs very smoothly overall and I think its something to do with the fuel delivery system......

Any thoughts would be appreciated

Hi I just moved to Kingston . I'm not sure where watertown is!

 

[xxBLOOD88SHOTxx]

They also throw codes when they go bad, and the car generally runs like crap like Xplod3r said.


Why don't you give the car a couple more mins to warm up, and see how it acts.

 

[XpL0d3r]

Yep, I'd def give it some more time to warm up.

My DC5 is the same way. I usually wait about a minute before going in the morning. Now that it's colder, if I increase the RPM's past 3k I can feel it hesitate slightly. Once warm it's fine though, so I just keep my shifts around 2.5k when it's cold, and I'm good to go.

 

[Trekk]

I had a problem like that once. It's some place on the forums here. My car would stumble when cold almost like it was out of fuel. The idle would surge up and down ( I added videos). Everyone said it couldn't be an the primary sensor, it wasn't possible and so on. They even challenged me into the core theory of and logic behind start up. Yet all I did was replace the primary sensor and my problem was solved. The car has run like a champ for over a year now.

Not saying it's your problem, but it sounds close. I used a Bosch sensor from Rockauto it was direct fit and only like $29.

 

[CIVICDXDUDE]

Replacing O2 Sensors

Thanks Trek,

Do you know if the top and bottom O2 sensors differ? Or do I just purchase two of the same kind?