A/F Gauge... what is the point?

[Gazord]

So I finally installed this autometer A/F gauge today (ordered it before I saw thread that it is junk).

I wired it up to the O2 sensor, not the ECU PIN # 60. The light(monitor) just runs the spectrum at idle and driving normal... pegs at rich under load. apparently that is what it is supposed to do according to the paper work...

"When the engine is at heavy load the monitor should indicate rich. At cruising load the monitor will appear to be bouncing back and forth between rich and lean. This is normal. The computer is constantly adjusting the air / fuel ratio for performance and low exhaust emissions." :wtf:

Given that, what is the point of this type of gauge? The data obtained from this instrument varies so vastly that I don't see how it could have any validity.

Is it just this certain brand of gauge that is trash, and another brand may have a better tolerance and more controlled readings?

Do you think I would get better results wiring it to the #60 pin? I thought I read some place to try wiring it up to second O2 sensor further down the exh. sys. has anyone done this?

The Vac/Boost gauge works okay, so I guess it wasn't a total waste. If there is no way for me to wire it up and get some more consistant results, then i'll probably take out the A/F and just get a voltage gauge or something to fill the hole in the pod. Maybe just buy a single pod, that will probably be cheaper and easier.

 

[perfworks]

this is why i recomend a FUEL PRESSURE gauge and a true wideband O2 sensor and module for proper tuning.
the gauge you got really does nothing for you . sorry for the critisism but its the truth

 

[turboge]

If you aren't tuning anything or running high boost or nitrous then you won't need it.

Your ECU is working and you are not making changes so you will see what it sees. If its sweeping your ecu is in closed loop, if its stuck rich its in open loop. If its red then your off the gas.

You just need to make sure that gauge stays green when your foot is on the floor.

 

[kwiktsi]

It is useful for tuning/monitoring at moderate performance levels, a bit useless for stock cars and/or highly modded cars. Still nice to have to keep an eye on things if you know what you are looking at..
Joe

 

[Gazord]

okay, I just wanted to see if it was maybe the way I wired it. Sounds like it is just a waste, unless you just want to know when you go into open loop. I know that anyway cause my dead spot goes away.

It was a waste of a little money. I should have done some more research before I ordered, but I learned from it. Good thing I didn't buy a more expensive one.

I was hoping it was going to tell me how the car was mixing the fuel through the rpm range. Since I have a nice dark black tail pipe I assume it is running quite rich. But it isn't going through any plugs, so I will just go with it and keep pumping the gas and tearing down the road.

I have to chunk that gauge though, it is just too annoying looking at all those colored lights. I hate useless frills... reminds me of a flashing cell phone antenna!

 

[dominoy2k1]

give you $30 shipped for it....

 

[Doric]

The biggest problem is that the way this gauge comes from the factory, it is displaying values based on 0 to 1.0 volts. In the case of most vehicles, the only really pertinent values for tuning based on the oxygen sensor are from about .80-1.0 volts. Should be old hat for most of you, but it warrants mentioning that a higher number indicates a richer A/F ratio, and a lower number indicates a leaner mixture.

Given this, any time you go into open loop, it better be in the green for you - in fact, on an uncalibrated gauge, if you see even just the first of the green LEDs, your car is running dangerously lean. So yes, for the most part, this is nothing but a light show and worthless for any real tuning.

But you didn't necessarily waste your money on this gauge. You can send it out to Gadget Seller for calibration. What he'll do is modify the gauge to display values based on a more precise voltage range - at your discretion or, if you prefer, his. He knows what he's doing. He also sells great digital O2 sensor displays.

Now, I'll also add that trying to tune based on O2 voltages alone is not exactly the most advantageous. If you get into forced induction, you should always monitor your fuel pressure and exhaust gas temperature. Now that wideband O2 sensors are becoming affordable, that is also a great addition to your setup.

There's more that I guess could be said, but I've almost written a novel as it is.

Cheers. Hope this helps.

 

[Apexi]

this is why i recomend a FUEL PRESSURE gauge and a true wideband O2 sensor and module for proper tuning.
the gauge you got really does nothing for you . sorry for the critisism but its the truth

smart man.

 

[perfworks]

The biggest problem is that the way this gauge comes from the factory, it is displaying values based on 0 to 1.0 volts. In the case of most vehicles, the only really pertinent values for tuning based on the oxygen sensor are from about .80-1.0 volts. Should be old hat for most of you, but it warrants mentioning that a higher number indicates a richer A/F ratio, and a lower number indicates a leaner mixture.

Given this, any time you go into open loop, it better be in the green for you - in fact, on an uncalibrated gauge, if you see even just the first of the green LEDs, your car is running dangerously lean. So yes, for the most part, this is nothing but a light show and worthless for any real tuning.

But you didn't necessarily waste your money on this gauge. You can send it out to Gadget Seller for calibration. What he'll do is modify the gauge to display values based on a more precise voltage range - at your discretion or, if you prefer, his. He knows what he's doing. He also sells great digital O2 sensor displays.

Now, I'll also add that trying to tune based on O2 voltages alone is not exactly the most advantageous. If you get into forced induction, you should always monitor your fuel pressure and exhaust gas temperature. Now that wideband O2 sensors are becoming affordable, that is also a great addition to your setup.

There's more that I guess could be said, but I've almost written a novel as it is.

Cheers. Hope this helps.

doric , two things
1. are you greek?
2. you touched on a point which is more relevant than any other. that is that the values displayed by a stock 2,3,4 wire O2 are very illusive to begin with . they is quite a delay in the way it measures the oxygen in the exhaust gases and then transmits them to the ecu. thus the narrowband sensor . anyway with out getting too technical i just want to add that your last comments were on point.

 

[Doric]

doric , two things
1. are you greek?

No, but I work in architecture (think Doric columns). Long story, but before I started putting a definition in my sigs, no one had a clue what 'Doric' meant.

2. you touched on a point which is more relevant than any other. that is that the values displayed by a stock 2,3,4 wire O2 are very illusive to begin with . they is quite a delay in the way it measures the oxygen in the exhaust gases and then transmits them to the ecu. thus the narrowband sensor . anyway with out getting too technical i just want to add that your last comments were on point.

Thanks.

There are a lot of things that should/could be said about tuning with and without a wideband O2 sensor, but I wasn't entirely sure that this was the appropriate context. Perhaps another thread...? I just spoke up to help Gazord find an alternative to pitching his new gauge. A calibrated AutoMeter 'blinky lightshow' gauge is useful for seeing at a glance what your O2 voltage is, so you can decide to take your foot out of the pedal or not. >shrug< Of course, there are other gauges that should be purchased first.

 

[perfworks]

gottcha

 

[trekv2]

so whitch ones should me baught first. boost, fuel pressure, exhaust temp? then A/F? im confused on what guages to buy

 

[perfworks]

so whitch ones should me baught first. boost, fuel pressure, exhaust temp? then A/F? im confused on what guages to buy

a boost gauge is good but i would go with a fuel pressure gauge also.
unless you plan on mods like increasing boost then i wouldnt go with anything else right now.
if you plan on going with major work then a wideband o2 and egt prope with gauge is a must.
again if you are staying with your stock setup then you really dont NEED anything.
but if you want some lookies then ..........

 

[AFaceInTheCrowd]

what about the uhh a/f meter from split second that terry is selling? that seems nice and useful

 

[perfworks]

what about the uhh a/f meter from split second that terry is selling? that seems nice and useful

if he isnt planning or doesnt have any mods done then whats the need for it.
the unit that terryis selling is a nice unit but not a true wideband.
similar to the greddy unit.
i just dont understand why you need it.
if the kit you are purchasing isnt calibrated to ensure proper fuel management then you should not use it.
if it is then you wont need it. again unless you are planning larger mods then the kit was designed for.

 

[Little Beavis]

If you want the rspeed that Terry is selling, I'll sell you mine (hardly used), probably can't even tell it has been used.

I'm going to get a wideband (one of these days). So, if you want it, PM me and we can talk. But as stated by perfworks, you don't need one if you aren't going to mess with the car. I needed mine to make sure it was "okay" when the turbo was installed. Don't really need it now, but I will when I take the next step.

 

[Apexi]

if you really want one...i wouldnt get an actual gauge..id get the Apexi Turbo Timer that has one built in..and its the better kind....numeric a/f..not blinky lights

 

[perfworks]

if you really want one...i wouldnt get an actual gauge..id get the Apexi Turbo Timer that has one built in..and its the better kind....numeric a/f..not blinky lights

yup what he said

 

[Doric]

There's also www.jumptronix.com - it doubles as a voltmeter. >shrug<

 

[kwiktsi]

a boost gauge is good but i would go with a fuel pressure gauge also.
unless you plan on mods like increasing boost then i wouldnt go with anything else right now.
if you plan on going with major work then a wideband o2 and egt prope with gauge is a must.
again if you are staying with your stock setup then you really dont NEED anything.
but if you want some lookies then ..........

If he doesn't plan to increase boost, why would a fuel pressure gauge be necessary on a stock fuel system'd car? I have mentioned earlier- for the cost a boost and o2 gauge combo can't be beat for moderate tuning. Hell, also like I mentioned, my talon is/was 487 whp and those are the ONLY two gauges I added to it. Wide band's kick ass for dyno tuning, but a regular AF gauge is nice for monitoring rich/lean at WOT at a glance on the street.. Let it dance all around at cruise, as long as it is where you want it at WOT, that is all that matters .
Joe