Hello everyone, I need to replace the Oxygen Sensor or O2 Sensor in my 94 Honda Accord EX due to getting poor gas mileage, so what kind of Oxygen Sensor do I need and do you know how much it costs?

 

First, this belongs in General Tech so I'll move it.

I'm pretty sure Denso makes the sensors for Honda, and you can get them at places like AutoZone... I'd get the kind with the wiring harness so you don't have to splice wires.

Finally, does your check-engine light come on? Get the error code. There's dozens of other things that can cause poor MPG. Why do you think it's your O2 sensor?

 

I have a Denso O2 sensor that I never installed on my 95 EX. I never had a chance to install it, because I found the TSX.

If interested, send me a PM.

 

I'm sorry that I posted the thread there because I was a new member and I didn't know the rules.

Thank you for telling me about the Oxygen Sensor. I'll get the one with wiring harness as you told me.

 

Thank you for telling me that. I'll contact you as soon as I have the $$ in hand because now I'm broke.

 

Are there any answers to Jim's questions? If a simple tune up (cap/rotor/plugs/air filter/ect) would do the trick then why not start there. Seems like you are jumping ahead, unless there is more info that hasn't been shared.

 

Sorry, I forgot to answer Jim's question... I only changed the Spark Plugs, other than that, I didn't change anything. The Air Filter looks clean and good. The Check Engine Light does not on. There is no lights come on but the Brake Light often comes on for a while and then off.

The reason I plan to change the Oxygen Sensor is because I read an article and it said that if the Oxygen Sensor is bad then the car gets poor MPG and the Idle Speed is not normal. Thus, I plan to change the Oxygen Sensor because my Idle Speed is always stay above 1000 even I adjusted/turned it to the lowest. My car runs and sounds normal. I could be wrong too because I only have a basic knowledge about car.

 

There are some things that you can do like clean the IAC and the FITV. You should also clean both sides of the throttle plate and the bore. Use throttle body cleaner. You can also tighten the FITV.

Once you do that stuff, you should properly set the base idle. Search around, because JimBlake has posted the steps to do that.

 

What did you adjust trying to lower the idle RPM? See my post on base idle over in the "DIY Answers" area.

Does the check-engine light come on for 2 seconds when you first turn on the key? (to rule out a burned-out bulb)

Bad MPG can be caused by a lot of different things in addition to the O2 sensor. But if the O2 sensor is original (17 years old) that's not a bad idea.

Spark timing might be off.
Valve-lash might need to be adjusted.
Vacuum leaks?

Finally, your "brake" warning lamp. Assume it's the same lamp that comes on with the handbrake? Low brake fluid will also set off that lamp. Check that out.

 

Hi Guys, thank you so much for your help or subjection. I'll try to follow Jim's procedures or do as you told me and then I'll come back here to let you know the result as soon as I can. I'm appreciated for your help.