Omg O2 Sensor

[Kevs]

Hey guys,

i have asked a few mates about o2 sensor, some of them said runs fine without one. I have run my sr over half a year now since i have a new engine drop in and what i found out is that the workshop that did the engine conversion didnt install the o2 sensor for me. what i saw is they blocked the o2 sensor hole with some washer or something like that, i having difficulties of starting the car every morning, i called them up and they said was the fuel pump too big and need the regulator... help me guys...

cheers

[Pal]

Don't need the o2 sensor but you need to tune the car around them, Otherwise it will suck the fuel and run rich . Do you have a fuel reg on it? The standard one will be fine if it's on there, even with the bigger fuel pump.

[Hanaldo]

Yeh my o2 sensor isn't connected in my car, runs fine without it. The car 'surges' a bit when cold and in closed loop, but fine other than that.

As for the fuel reg, they are a waste of money. Completely unnecessary if you have correct size injectors.

[Pal]

That's aftermarket fuel regs, not the standard one. My o2 sensors were turned off as well but wasn't happy with how the car was running so bought new ones and turned them back on

[JonnoHR31]

o2 sensors dont affect startup in any way whatsoever

[GTS-t VSPEC]

Personally if it's a street car than I'd have the 02 Sensor working, as closed loop control will give you much better fuel economy.

[Hanaldo]

That's aftermarket fuel regs, not the standard one.

Yeh that's what I meant.

Personally if it's a street car than I'd have the 02 Sensor working, as closed loop control will give you much better fuel economy.

Depends how it's tuned. If it is tuned properly around cruise then you may get better fuel economy. I get 600kms to a tank if I drive nicely, 550ish if I drive around on boost a lot.

[Pal]

Depends how it's tuned. If it is tuned properly around cruise then you may get better fuel economy. I get 600kms to a tank if I drive nicely, 550ish if I drive around on boost a lot.

i get 350 to a tank, maybe need to turn one turbo off

[GTS-t VSPEC]

Depends how it's tuned. If it is tuned properly around cruise then you may get better fuel economy. I get 600kms to a tank if I drive nicely, 550ish if I drive around on boost a lot.

Yeh my o2 sensor isn't connected in my car, runs fine without it. The car 'surges' a bit when cold and in closed loop, but fine other than that.

So other than the surging its all good ?

[Kevs]

so you guys mean running without o2 sensor doesnt really matter? then i have to look at my fuel pump, i dont have an aftermarket fuel regulator which makes the cold start really hard.... crank a few times before start... i surprised that honaldo runs 550-600 for a tank... mine only runs 350-400 for a tank with running stock boost 6-7 psi. ALso my carblowing smokes when i hit boost... wtf? you guys recon my turbo is weak now?

[GTS-t VSPEC]

What ECU are you running ?

Personally I'd install the O2 sensor, you'll get better mileage.

Have you checked your spark plugs, chances are they're coated from running too rich.

What color smoke is it blowing ?

[Hanaldo]

So other than the surging its all good ?

Well as far as I can associate with the O2 sensor yes... Car has gremlins, I'm missing about 100rwhp and 500rpm of response, but can't see that relating to the o2 sensor. Still searching for an answer to that problem. I also get a lot of reverberation, but again that is to be expected having an AFM in front of a big turbo.

As for the 'surging', that doesn't really describe it. It's not like a fuel surge you get from running low on fuel. It's like when I'm cruising on decel, using the engine speed to maintain roadspeed going down a hill or something like that, it sort of feels like I'm tapping the brake slightly and then taking it off. It slows down a tiny bit then picks back up. If I touch the accelerator at all then it doesn't do it. Given it only does it when cold, I imagine it is sensor related. Can only think of either TPS or o2 sensor, and seeing as my o2 sensor is unplugged then it makes sense.

/long winded explanation

[Pal]

Think it's just a skyline thing, my gtst done it as well and so does the gtr