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Inconsistant Wideband Readings

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Old Sep 22, 2015 | 08:10 PM
  #1  
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Inconsistant Wideband Readings

I'm stumped on what would cause this situation.
My wideband readings in first gear don't match what I see in 2nd and 3rd for a given map and rpm.

For example launching from a stop, map 95+, tps 80%+, 3500 to 5500 RPM, has the AFR bouncing around 10.8, while in 1st gear, however in 2nd and 3rd over the same rpm range, same map, AFR is more like 13.5

The ECU doesn't know what gear I am as there is no sensor on the gear selector. (Manual Transmission)

I'd like to add more VE to bring the AFR closer to 12.8 for when in 2nd and 3rd, but not sure how to do that without making a very rich condition even worse in 1st.

Any creative ways to deal with this?
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Old Sep 23, 2015 | 08:24 AM
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Inconsistant Wideband Readings

What is the injector duty cycle (DC%) as you run up through the gears? Is there enough fuel in the tank to prevent the pickup from being uncovered? Does the fuel pressure hold the whole time?

You can enable the N/V ratio option and fill in the N/V table This will allow you to use less PE spark advance in each higher gear. That will affect the reported AFR in the exhaust.

RBob.
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Old Sep 23, 2015 | 05:55 PM
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Re: Inconsistant Wideband Readings

As per the other thread, I am hitting 100% for about 3 data points, then it drops back to 65% and as it revs it goes up to 85%. Fuel pressure is steady at 12. Tank is full.
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Old Sep 23, 2015 | 07:06 PM
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From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Inconsistant Wideband Readings

With only running 12 psi now you have lots of headroom with increases in fuel pressure.

RBob.
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