civicboy420

Hey I have a 98 Civic and it gets terrible gas mileage. Highway driving I'm down to a quarter tank and only gone 179 miles. I took it to Autozone today and had them do a scan. I'm getting codes p0153 (sensor 21 slow response) and p0133 (sensor 1 malfunction). I have a DC header, intake, and exhaust. I googled and found so many things that could be the cause. Has anyone had this problem? Thanks

NotARaCist

iTrader: (1)

Considering you don't have a bank 2, I'm curious how they pulled P0153...but P0133 is easy. Make sure your primary O2 sensor is plugged in. If it isn't, plug it in. If it is, it's time to do some diagnostics. Unless someone beats me to it, I'll try to post the related FSM pages for you when I get home.

civicboy420

I'm sure I have an o2 sensor after my cat

Former User

Post the Civic trim and engine.

P0153 is not a code for your car. Jump the service connector to pull the codes yourself.

NotARaCist

iTrader: (1)

The O2 sensor after the cat is your secondary sensor. For your car, there is one "Bank 1 primary" sensor, and one "Bank 1 secondary" sensor. There are no bank 2 sensors. The O2 sensor after your cat also has nothing to do with how your car runs. There's a reason I specifically said your primary O2 sensor.

civicboy420

Ex Coupe. My dealer replaced the primary o2 sensor twice already. I don't see how one o2 can cause 2 codes. Thanks for the info guys.

civicboy420

Also for code p0153 the recommended action was to replace the o2 sensor or fix the wiring same with the primary

Bently_Coop

If you end up replacing the sensor/sensor's use a Denso or NTK.

Bently_Coop

You need to find the reason this is failing. O2 sensors don't usually fail on there own.

NotARaCist

iTrader: (1)

You need to stop and listen to what RonJ and I have both told you. There is only ONE primary O2 sensor on your car. One. Singular. Un. Uno. Een. Një. մեկ. P0153 is a code for Oxygen Sensor Circuit Slow Response (Bank2, Sensor1). You do not have a bank 2 O2 sensor. If they pulled a P0153, either they're shitty at using their code reader, their code reader is shitty, or your ECU is somehow magically throwing a code it doesn't know how to throw.

Are you going to listen to us now, or do we have to tell you a fourth time?

civicboy420

This may not have anything to do with it, but I switched to synthetic oil last month and checked the level today and I was out of oil. Maybe whatever is causing me to lose oil is messing with the o2? I have no clue.

NotARaCist

iTrader: (1)

Are you burning it, or leaking it?

civicboy420

I'm sorry I'm listening. I just think it's weird. My dealer is trying to say it has something to do with my header. I don't know. Sorry to waste everyone's time. Thanks again.

civicboy420

I don't have any leaks what so ever. Gotta be burning.

civicboy420

I went to Autozone for the scan. I have an appointment at Honda tomorrow for my factory alarm not working. I'll have them scan my codes again. Hopefully only one comes back.

NotARaCist

iTrader: (1)

You're burning a full engine worth of oil in a month (however many miles that might be), and it's damaging your O2 sensor. The fact that the dealership wants to blame your header, and not the failing engine, should tell you that it's time to find a new shop to work on your car. The fact that you're burning enough oil to damage your O2 sensor, and you aren't saying anything about blue smoke, should tell the rest of us that you need to pay better attention to the well being of your car. Why are you paying the dealership to do it, anyway? It's literally a 15 minute job, with only one special tool that you can buy at any parts store for like, $10.

Unplug and remove your O2 sensor, and post a picture of the end of it (the part that goes into your header), so we can see it's condition. If the oil burn is causing the failing O2 sensors, it'll be pretty obvious.

civicboy420

Sorry I forgot to mention I didn't pay my dealer to replace the o2 he replaced them before I purchased the car. I already knew there was a situation with the o2 sensor. I know how to replace them. I can do most things on my car myself. I will take a picture on Saturday when I have time and keep you guys posted. I have no blue smoke coming out of my exhaust.

civicboy420

I just realized I have a powertrain warranty. I'm taking my car to the shop to have them diagnose the oil and O2 sensor situation. All internal parts are covered. They said the teardown is covered unless there is a lubrication failure or rust. What is lubrication failure? I keep oil in it. It may have gotten low but there was still a couple quarts left.

eghatch9295

iTrader: (1)

yeah, dont tell them you ran it low. tell them you have to keep adding. they will look for any excuse to not honor that warranty.

civicboy420

Thank you!

civicboy420

I got my car back from the shop. I need to replace the o2 sensor. They told me it has an oxygen sensor and needs an air/fuel sensor. That is why I'm running rich and losing massive amounts of gas. I can't find an A/F sensor for my 98 Ex anywhere. Only standard oxygen sensors. I found an AF sensor for a 98 HX, would that be compatible with my EX?

NotARaCist

iTrader: (1)

Whatever shop you took it to is staffed by ******* idiots. Ignore what they told you.

civicboy420

If thats the case then why would I have a code for an o2 sensor and going through gas like crazy? They performed a leak down, compression and smoke test. The only thing they came up with is oil gunk on spark plug 1 & 3. Not getting enough spark, may need a hotter plug.

Former User

Why didn't you post the engine as requested?

Also post the ECU code (label on ECU).

NotARaCist

iTrader: (1)

Do you know the difference between an O2 sensor and a wideband air/fuel sensor? Your car does not use a wideband sensor, unless there's some required information that you have failed to provide us. So either you didn't follow the rules, and still aren't following the rules, or the shop is staffed by ******* idiots.

Give us all required information. If you're just going to question everything we tell you, completely ignore all advice given, and let the shop suck your wallet dry, then don't insult us by wasting our time any more than you already have. This forum exists to help with technical DIY work. That's what we do. We don't do "help me second guess the shop".