I have an air/fual gauge installed, and I spliced it into the purple and white wire on the computer. It turns on and everything now, but its moves with my rpm, when i start the car it is maxed, and when I accelerate it goes all the way back to rich, and maxes itself out? Is that normal. I searched and didn't find anyting. Thanks.

 

When you start the engine, it should be right in the middle..... system will read 450mV. As the sensors warm up, it will drop to "lean" (assuming you still have the AIR system), and then when it goes into closed loop, the gauge should become a psychedelic light show, sweeping rapidly back and forth between lean and rich. When you go to WOT, it should read in the "rich" area. Realy doesn't tell you too much, other than that the sensor is working.

 

Your air/fuel ratio gauge is using a signal from your stock O2 sensors to drive the gauge, that's why you'll get the readings Rich described above. The stock O2 sensors are only accurate in a narrow range, centered at 14.7 air/fuel ratio. This valve is selected by GM to maximize fuel mileage for part throttle driving, but is way too lean for performance driving. That's why GM has a fuel enhancement mode for WOT resulting in rich conditions (as compared to the 14.7) but a more desired air/fuel ratio for hard acceleration.

 

I buddy of mine has a A/F ratio gauge in his car. It had to be the most annoying gauge I've ever seen. All it does it move around sporadically and tell you nothing. I say cut your losses and get something a little more worth while...like a oil pressure gauge or a temp gauge.

 

i use mine mostly for when im spraying to make sure it doesnt shoot over to red/lean. this basically just tells me that my nitrous pressure regulator is working. i had the vacuum line pop off the fuel pressure regulator a couple of times before (while spraying), and my a/f guage went lean, so i hove found mine to be useful. i ziptied my vacuum line on my FPR and it hasnt come off since. it'd be nice to get a wideband but dont wanna spend that much