sauceman

Earlier this week, I did a small write-up ( https://acurazine.com/forums/showthread.php?t=20121 ) on my trip down to Florida, and how I had encountered a few problems, such as running on 2 and 3 cylinders, and the check engine light coming on shortly afterwards.

So I got it looked at Thursday at the dealership, and it's a faulty primary O2 sensor What is bizzare about it is that they performed tests on the O2 sensor, and it responded normally to all their tests.

We then decided that they'd clear the code from the ECU, and until my next service (in 2 weeks) I would drive around with it, and see if the ECU would throw a CEL again. We thought, maybe the sensor had encountered a problem, and was ordering the ECU a wrong mixture, either too rich or too lean (I tend to believe it was too lean, because it looked as though the cylinder #1 was misfiring), but wasn't experiencing any terminal problems.

Anyway, yesterday the CEL came back on, so we'll have to replace it. Only, this time at least, I didn't have to go around driving on 3 cylinders.


It looks as though the oxygen sensors don't like the cold weather, because last year, at that time of year, and with weathers around -20°C (0°F) I had to replace the seconday O2 sensor. Only it was under warranty back then. Now it's not: $231.00 + tx. Ta-tching!! ...

JTso

iTrader: (2)

Wait... I thought emission devices are under a longer warranty period and O2 sensor should be considered an emission part...

JeffTSX

That's what I though too

sauceman

Yes, they're under a 5-year, 100,000km warranty.

I'm now at 149,000km.

CGTSX2004

iTrader: (1)

Damn!! Almost 100K miles... You've got to have the highest mileage TSX by a wide margin...

TinkyWinky

Being the sarcastic a-hole that I am, I was about to make a comparison to my old VW, which had a faulty O2 sensor not more than a month after purchase.

To quote CGTSX2004, Sacre Bleu!!!!

sauceman

(the grin is for all the hours of fun I've had with this car so far: I got more than all of you, hehehe...)

iTimmy

Aren't O2 sensors part of preventitive maintnance at some point? I suspect cold weather had less to do with there malfunction and more to over all use- this is of course pure speculation. I just find it hard to believe cold weather would ultimately be the reason they were not functioning properly.

JTso

iTrader: (2)

I wonder if the O2 sensor's built-in heater circuit failed... Do you know what the error code was? That would help determine what happened.

sauceman

Nope. They aren't (or shouldn't be) accounted for parts that would be subject to maintenance like brake pads or such. If they were, they wouldn't be covered by a prolonged warranty.

sauceman

Gonna check it out, but I don't believe it would be the heater, as the failure occured after hours of driving. That did, however happen on my 95 Accord.

dom

Sauceman is the TSX guinea pig

So could any engine damage have occured by running on 2 cylinders?

I'm at 60,900km's but since I got the second car I've only put a few hundred K on the TSX so it looks like my powertrain warranty is going the full 5 years, thank god.

sauceman

It sure couldn't be good for the engine, especially if the misfire was because it was running too lean.

But we didn't run it for miles and miles that way, so I don't believe it would have really damaged the engine if anything.

jlukja

Are you replacing it yourself? We had the O2 sensor go bad on my wife's Civic. Dealer wanted $450 to do it. I bought one at another dealer for $191+tx. and did it myself in a little over an hour. On the Civic it was waaay easy.

sauceman

It's almost as easily done as changing a sparkplug. If they ask too much for the labour, I might do it myself. I just don't feel like giving myself the hassle. I don't have a garage or a lift. But if I have to...

IMO, 450$ is outrageous.

zumzum

The dealer should pay for the replacement. The CEL on my car went off 4 times within 1.5 months and they replaced everything no charge. Good luck!

sauceman

Your warranty was still valid. Not mine.

sauceman

Well, Friday, I got the O2 sensor replaced, and the car went fine, just as it did previously.

BUT, yesterday, coming back from an ice-fishing day, teh F***'ing CEL came back on again.

Gonna get it checked tomorrow, hopefully.

sauceman

Well ain't it quite the pile of :

This time, the CEL means there is an insufficient flow in the catalyst, inducing a bad reading to the ECU.

Meaning, the catalyst is partially obstrued, and needs replacement.

dom

Catalyst?

CGTSX2004

iTrader: (1)

Uh...maybe just have them remove the cat completely...

dom

Ok, I figured the catalyst was the Catalitic converter but wasn't entirely sure.

Sauce, this isn't looking good for the TSX

sauceman

You're right: Catalitic converter.

Indeed, it's not too good. And it is caused usually by one thing: High oil consumption, so we're going to monitor it on my car, see what's the deal with it. I estimate it to be around 1 quart per 4000km. But quite honestly, I have never checked it, or worried about it much before.

JTso

iTrader: (2)

Is the error code for the secondary O2 sensor? It sounds like a perfect opportunity for a high flow cat.

sauceman

I dunno about the code. I agree with you for the high-flow cat, but not for now.

If the problem arises again though, it will be test pipe time. Permanent.

JTso

iTrader: (2)

You can't really use a test pipe on an OBD2 car because the secondary O2 sensor is expecting a certain reading after the cat. I believe it's the same reason you are getting the CEL. However, you might be able to use what's known as O2 simulator which mimics the reading and feeds it back to the ECU to prevent triggering the code. In which case, you won't even need the secondary O2 sensor, so a test pipe is possible.

Edit: check this out. http://www.o2sim.com/

sauceman

Thanks JTso, once again, invaluable info!

Alin10123

So what's the scoop? Did you get that second CEL fixed up? come on! give up an update! we're curious here. lol

Mugenpwp

Sorta bringing this back from the dead.

My primary sensor went out. Its dead. I wonder will the dealership warranty the 02 sensor even though im running an aftermarket header?

Or perhaps i shouldnt waste time since they will blame the header for it breaking?

PACman

The primary O2 (air/fuel mixture sensor) is easy enough to replace on your own, without having the dealer charge you for labor.

Take a look in your manual under warrantees, cause it'll say emissions related item have a 7/70K or 8/80K mile warrantee depending on what items.

moda_way

I seriously doubt it will be warrantied since it had to be taken out in order to put the header on. but good enough excuse.

brock1270

P2AOO came up says "p2aoo Oxygen sensor (02S) 1, bank 1 - range/performance lntake/exhaust leak, fuel pressure, wiring, 02S Heated oxygen sensor 2 bank 1" can anyone tell me where that is located?? Thanks If I replace the sensor will that take care of the problem?