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General Wideband o2 reading really rich.

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Sjd6795

Proven Member
614
121
May 14, 2014
Wilsonville, Oregon
Just got a sensor installed and my wideband gauge hooked up. At idle the car sits around 13.5 then cruising it's really rich at around 10.3-10.5. When I come up to a light and idle it's around 11.7 idle however once the car sits idle for a while it will go to 13.5. WOT it pegs at 10.0 and I assume it would keep going if the gauge could read lower.

Original my car was tuned at 15 psi on a 14b, I swapped to a small 16g and still at 15 psi. I understand the car needs to be retuned and I am working on getting open port cables for my ECU. But what I don't understand is shouldn't the car be running leaner since I am flowing a lot more air with the 16g? I also changed to a FP intake and FP exhaust manifold.

If anyone can educate me further it would be appreciated and also any solutions to why it would be reading really rich. Here is a picture of my sensor placement. I placed it right before the flex section and at a slight angle to prevent moisture from sitting on it. I don't think it being immediately after the bend would change the readings that much right?
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My guess is the car is running rich which is why it's reading rich. How is the car tuned? Get an o2 sensor from Rockauto.
It was tuned by English racing my car has a black box ecu. It hasnt been tuned since changing the turbo and other parts but those only increase airflow so running that rich on stock injectors just seems odd.
Thank you.
 
I'm confused. If you just installed your WBO2 how do you know what the AFR's were before the install? I'm with @Vegas smith
Because before the install the car was tuned by english racing on the dyno.. A very reputable shop and probably the best in the west coast with our cars it was not rich with the 14b, stock intake, stock exhaust manifold. And yeah Vegas pointed out the very obvious thing... duh the car is running rich if the wideband says it is.

That doesn't answer my questions I had though, with the increase in airflow with a larger intake pipe, turbo, and exhaust manifold should it not be more on the lean side? I only have a rewired walbro 190 and stock injectors there is no way it should be keeping that rich with 450cc at 15 psi. Any leaks has previously been taken care of I replaced vacuum lines, and resealed all of my intercooler couplers.
 
If your front O2 sensor is bad it could cause the AFRs to be off.
That's what I am thinking as well, every so often I get a CEL that will come on and off literally in the span of like 0.5 seconds. It never stays on long enough to read or even store a pending code, I don't know if this would be the o2 on it's way out or the fact the car is rich and it has some occasional knock throwing a cel. I'm not sure if it was originally tuned to throw a cel on knock though.

I just ordered my openport 2.0 cables and have ecuflash / evoscan, hopefully next week I will be able to get some logs on it and tune accordingly.
 
So what were your AFR's before you installed the WBO2, 16G, & FP exhaust manifold?
 
It's possible your wideband needs to be recalibrated
Because before the install the car was tuned by english racing on the dyno.. A very reputable shop and probably the best in the west coast with our cars it was not rich with the 14b, stock intake, stock exhaust manifold. And yeah Vegas pointed out the very obvious thing... duh the car is running rich if the wideband says it is.

That doesn't answer my questions I had though, with the increase in airflow with a larger intake pipe, turbo, and exhaust manifold should it not be more on the lean side? I only have a rewired walbro 190 and stock injectors there is no way it should be keeping that rich with 450cc at 15 psi. Any leaks has previously been taken care of I replaced vacuum lines, and resealed all of my intercooler couplers.
You had English Racing tune a basically stock car?
 
It's possible your wideband needs to be recalibrated

You had English Racing tune a basically stock car?
It's a 97 GSX with a black box ecu, 2.3l enigne, FMIC, and 15 psi on a 14b. So sort of stock but obviously much different a stock 2g.

It now has other aftermarket parts as well.

Never heard of re calibrating a wideband before, I'll look that up.
 
I take it you had no idea of what your AFR's were before the WBO2. From your first post your AFR's look factory normal to me.
This is the factory Hi-Octane AFR's settings map.
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