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Hi guys just installed my VG30 Highflow turbo.

Everything was running great until it started to have start up issues like idle hunting.

But besides that it was great on fuel and power.

I tried to figure out what the startup issues were and I found out that we forgot to plug in the oxygen sensor on the dump pipe.

So I plugged that in and it sorted out all the startup issues.

But now though its chomping on petrol and its not running as great as it was before.

Do you really need the oxygen sensor on the dump?

Any comments would be great.

Cheers

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https://www.sau.com.au/forums/topic/188599-is-oxygen-sensor-needed/
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on a standard ecu you do because it uses a closed loop idle and low load O2 correction. car runs abit crappy without it, not very fuel economic. you can eliminate the need for it in most aftermarket standalone ecu's.

when you say it wasn't plugged in was the electric plug not connected or the O2 sensor not screwed in at all?

Thanks for the reply.

Well actually its the exact opposite. Car runs great without it.

More power everywhere and fuel economy was great.

200kms of driving on a bit over a quarter tank.

I was talking about that the electric plug wasn't connected.

Thanks for the reply.

Well actually its the exact opposite. Car runs great without it.

More power everywhere and fuel economy was great.

200kms of driving on a bit over a quarter tank.

I was talking about that the electric plug wasn't connected.

Might need replacing, they dont like being in the exhaust stream without the heater working, tends to clog them up.

Sorry but I don't quite understand what you mean by that?

Want to explain what your on about?

So you think the oxygen sensor plug needs to get replaced?

Well isn't it if it wasn't working it wouldn't be changing how the performance of the car even if it was plugged in or not?

Sorry don't quite understand what you mean mate.

Sorry but I don't quite understand what you mean by that?

Want to explain what your on about?

So you think the oxygen sensor plug needs to get replaced?

Well isn't it if it wasn't working it wouldn't be changing how the performance of the car even if it was plugged in or not?

Sorry don't quite understand what you mean mate.

No, i mean the oxygen sensor it self. Shortens their life by having them in the exhaust with the heater not connected. The substrate gets coated and they no longer work. When an oxygen sensor is on its way out, they slow down. They are supposed to reach a set amount of oscillations in a set time frame. If they take longer to react then the ecu sees that as not delivering enough fuel and will keep adding more until the voltage swings. They also eventually decrease the voltage output, ecu sees low voltage, takes that as a lean mixture and will keep dumping fuel in.

Explained better?

Hey just wondering whats the worst thing that happens when there is no oxygen sensor?

Because without it, after a few minutes the car us running when u drive it.

Did I mention I have a remapped ecu for this turbo.

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