Breathe damn you, breathe!

New Years Eve – I should have been putting some ice on the Coronas, party pies in the oven and some resolutions on my to do list in preparation for howling at the moon around midnight. Instead I was driving from town to town playing a game of ‘Do I have enough juice to make it to the next service station?’

AKA Now that I’ve finally gotten around to replacing my oxygen sensor in the Stagea, lets make sure it’s doing what it’s supposed to be doing.

When working, an oxygen sensor/o2 sensor/lamda sensor sniffs out how much oxygen is flowing through your exhaust and shoots a signal to your Engine Control Unit (ECU) which then adjusts the air and fuel mixture to the best level. In basic terms it helps with fuel consumption. They’re supposed to be changed over every 40,000ks or so but I’m yet to own a car where someone has done this before me.

When it’s not working, chances are you’ll be wondering why you weren’t getting so many ks out of your full tank like you were before and occasionally why your ride is running like a rich pig. Some people report a rough idle as well but for me I suspected something was a bit odd when I was averaging 17/18 litres for every 100ks. Sure the Stagea is a heavy beast but not that heavy – not even my 1989 Rx7 wasn’t that bad. And when you’re using this thing as a daily driver, having it drink like an unwanted uncle at your wedding is not ideal.

I had it confirmed via the diagnostic mode – a quick bridge pointed out my oxygen sensor was either dying or had completely snuffed it (the flashes of the check engine light don’t really differentiate – it’s just listed as HEATED OXYGEN SENSOR SIGNAL CUT – which I’m assuming must mean ‘Yeah, it’s lunched’.) So it was time to wrench the old one old, screw a new one in and pray that the fuel gods would smile on me once again.

Of course for a replacement there’s a few options – a factory version is close to a couple of hundred dollars, there’s also the Repco oxygen sensor for the EL Falcon that amazingly seems to do the trick (OX207) for around 80 bucks but I also found a universal three wire oxygen sensor for the RB25 Neo engine on eBay for a low forty shekels – and given my budget (not much) I decided that was the way to go.

Now depending on what you drive and the location of your oxygen sensor, sometimes swapping over a new unit is a 10 minute job. When I first tried this in my 2000 Stagea, it took me an hour with various tools to discover that the angle the sensor is installed is an absolute nightmare. I bent a couple of cheap wrenches to try and make them fit, still didn’t have enough room. I tried some locking pliers too and just ended up crushing the old one but not actually removing it – if it wasn’t dead before, then I’d just spent a full hour giving it its last rites. Yeah, I’d advise not to do this:

dead oxygen sensor

How not to remove an oxygen sensor..

My father in law took a look and suggested custom making some kind of removal tool by welding together a couple of old sockets. But then he suggested maybe shopping around for a proper removal tool. Wise man that Baz.

The first store I tried had a deep socket with a provision open for the heater wires but it didn’t fit over the 22mm nut of the new one so the guy suggested taking the entire dump pipe out and wrenching it off on a bench (so much for a 10 min job) “Welcome to Japanese imports” he laughed as I walked out of the store. Thankfully the next place had a proper tool that would fit over both the nut and the wires on a dusty shelf out the back – all for a low 12 bucks. Bargain!

Oxygen sensor removal tool

Two seconds of effort. Why didn’t I buy this first?

Coupled with a 1/2 inch drive and a small extender, the old now completely dead unit came out incredibly easy and we spent more time crimping the new wires in that we did wrenching everything out. Seriously, buy yourself a proper tool and save yourself at least an hour of frustration.

Did we mention they’re available through Amazon?

 

As for the testing? I took the family out for a picnic (and an opportunity to test the new oxygen sensor) and was quite happy to get a little over 120kms out of the last quarter tank. This was far more than usual and I’ll be a testing a full tank shortly in the aim to get more than 370kms that I did with a cooked sensor.

So, is it time to change your oxygen sensor?

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