Air/fuel ratio gauge

[Daryl]

Having an air/fuel ratio gauge installed is new to me. Mine bounces all over the place. For instance, today driving home on the freeway it bounced around rapidly between roughly 14.2 to 15.6

Is this how they function? Flashing and blinking numbers very quickly?

 

[lwarrior1016]

Yes, they will do that as they are targeting a certain number. It will oscillate over and under the target. When you go wide open throttle, it should go rich (12.2 ish on an NA engine, but that is different car to car) and stay there until you let off the throttle.

 

[Daryl]

Ok. Got it. But it never “settles” on a number it bounces around like a whirling dervish. Makes me wonder the actual value of it since it doesn’t ever display anything constant

 

[lwarrior1016]

It won’t be constant. It’ll average between the high and low number. Just like fuel trims on a stock system, they aren’t ever steady.

 

[cobrajeff96]

Yea, for instance when you are just cruising steady, it'll be centered on the stoic (14.7) but that's just one variable. You suddenly let off the gas completely as in just starting to coast and slow down, it'll suddenly spike higher into the 15s and then quickly level back off to stoic. You're trying to account for variables that are out of your control so I wouldn't worry about any of it. The real key is when the foot is down and real power output is being applied. Then the readings become important, especially if you have the guage in there for boost applications, or even nitrous.

 

[duh09]

I’ve got a wideband in my car feeding info to the Microsquirt and do not want to see a gauge on it for that very reason.

Tuned to not go pop, I don’t want a light show in my face to stress me out all the time lol.

 

[Daryl]

Ok, so what the gauge is doing is “normal”? Then I won’t worry about it as recommended! Thanks guys, I appreciate the feedback. Thought maybe the installation was messed up.

Thanks again Warrior & Jeff! Cheers

 

[Michael Plummer]

Do you have a wideband or narrowband air/fuel setup? And which brand did you purchase?

Thanks
Michael Plummer

 

[Daryl]

I don’t know wide or narrow. I purchased the gauge bezel with the auto meter air/fuel ratio and oil temp gauges from Maximum95 after he scrapped his car.
Is there a way for me to decipher what I have? As I alluded to earlier, I have NO knowledge or understanding of air/fuel ratios.
I’m very willing to learn, so if you can help… Thanks!

 

[Daryl]

Quick Google and I learned I have a wideband because the gauge actually flashes numbers. I also learned that a narrowband doesn’t have numbers, just a needle that will point to “Lean, Stoich or Rich”.

 

[cobrajeff96]

If it's a five-wire sensor it's a wideband. Four-wire is narrow.

 

[Daryl]

Correction: I misspoke. The AFR gauge is AEM; the oil temp gauge is the AutoMeter.

 

[Daryl]

Now I’m all over the place looking at You Tube videos and Googling questions to see if maybe ny gauge or O2 sensor it came with is bad. All I’m getting is CONFUSED!!

 

[badass98svt]

Why did you install it?

 

[Daryl]

Why did you install it?

Kid in a candy store! Impulse purchase. 1. Thought it would look cool, and 2. thought it would help when I take it in for a tune

 

[badass98svt]

Just take it off and sell it and recoup some of the money you paid if you don't use it though I mean.

 

[Michael Plummer]

I'm assuming you have a wideband, not a narrowband, so I will leave that up to you to confirm.

I'm not familiar with your setup, but a wideband air/fuel ratio meter is commonly used in modified or performance vehicles where the stock narrowband sensor may not provide enough accuracy or resolution. The wideband allows for a more precise measurement of the air/fuel ratio across a broader range, typically from lean to rich mixtures. This information is useful for tuning aftermarket engine management systems, optimizing performance modifications, or monitoring the engine's health. The bouncing you mentioned in your first post is expected, provided you are at part throttle cruise. This information is an average air/fuel ratio taken from that bank. For a V8 engine, you should have a wideband for the other bank because it's important to know what the other half of the engine is also doing.

I just noticed you stated this was an impulse buy, and that's fine; your car, your money, do whatever you like.

Good luck
Michael Plummer

 

[Daryl]

I'm assuming you have a wideband, not a narrowband, so I will leave that up to you to confirm.

I'm not familiar with your setup, but a wideband air/fuel ratio meter is commonly used in modified or performance vehicles where the stock narrowband sensor may not provide enough accuracy or resolution. The wideband allows for a more precise measurement of the air/fuel ratio across a broader range, typically from lean to rich mixtures. This information is useful for tuning aftermarket engine management systems, optimizing performance modifications, or monitoring the engine's health. The bouncing you mentioned in your first post is expected, provided you are at part throttle cruise. This information is an average air/fuel ratio taken from that bank. For a V8 engine, you should have a wideband for the other bank because it's important to know what the other half of the engine is also doing.

I just noticed you stated this was an impulse buy, and that's fine; your car, your money, do whatever you like.

Good luck
Michael Plummer

My engine is modified: 347 stroker; Scat rotating assembly; AFR 165 heads; Crane cam; BBK throttle body.

Do I understand what you said correctly I.e., By “bank” do you mean each side of the V8? Forgive my ignorance… I’m learning!

 

[95opal]

My engine is modified: 347 stroker; Scat rotating assembly; AFR 165 heads; Crane cam; BBK throttle body.

Do I understand what you said correctly I.e., By “bank” do you mean each side of the V8? Forgive my ignorance… I’m learning!

Yes a wideband 02 ito read cylinders 1-4 and another wideband on cylinders 5-8

 

[Daryl]

So I’m only getting half the story.