I just installed a AutoMeter A/F monitor last night. Connected the wire from the O2 sensor up to it and power and ground.
The guage does not hold a steady position. It roams around from lean to rich. Even at a steady throttle position, cruising on the highway at 2200 rpm.

Is this correct? Should it be steady? What does your A/F meter do? My ECM not working? By the way, the car runs great.
350TPI, 5 speed, stock FP, 25lb. injectors.

Thanks

 

The A/F ALWAYS gets adjusted by the ECM therefore you will NEVER get a steay ratio (maybe at WOT). What the guage is doing is absolutely normal.

 

Exactly. A/F guages are just pretty light shows. There is practically nothing useful about having one IMO.

 

If the A/F gauge is useless, how do you know if the ratio is correct? Looks like I just wasted more money on my ride.

 

You can't tell with a meter. The Block Learn can be way off but
your meter will still dance for you as long as the Integer is mobile.

So yea, you just wasted some more money on your ride.

What I have always wanted is a way to tie a meter like that
to the Block Learn reading. Then you would know exactly what
was going on.

 

Yeah swapmaster, it'd be sweet if somebody developed something like the TR guys have that reads data directly off the ECM board. Then the sky is the limit once you have a set-up like that.

In answer to the question as to how you know your A/F ratio is correct. Well, for idle/part throttle you figure this out with a scan tool to read the BLMs to figure out how far from the stock fuel tables you are.
For WOT you can use a WB O2 sensor, plug cuts, and/or intuition to dial this in for best performance.

The only thing an O2 sensor will tell you is if you are grossly rich or lean, or kinda ballpark at WOT. Closed loop it's always going to dance unless you're so far off that your BLMs have run out of room to move.

If none of these terms made sense, search the DIY PROM board to get the lingo down.

 

On the opposite side of "Its no good" and "you wasted money on your ride". A heated 02 might make it a tad more accurate for what you're working with.

 

For a quick check of A/F ratio, jumper the ALDL pins !&B, start the engine (to put the ECM into diagnostic mode), drive the car and observe the SES flashes. The On/Off means Rich/Lean; equal duration flashes means right on, at steady speed. If the flash rate doesn't settle down to about 1Hz in a minute or two after starting the engine, service the O2 sensor.

Observe your A/F gauge. At WOT it should go to Rich; at part throttle it should swing between Rich & Lean, as does the SES in the above test. So, yes, you can use the A/F gauge to monitor conditions, though but not for detailed info.

As mentioned, use a scan tool for details.

 

you ahhh gonna be sellin that guage? i got a friend whos actually looking for one

thanks