My setup: Stock 99 Si T3/T4 turbo, 450cc injectors, VAFC hack (around 38-40% across the board)

Autometer AF gauge (i know, I have a wideband in the mail, but im only driving this car another month) I would be driving, and then all the sudden i look at the AF gauge and no leds are light up. While still looking, the lean red led pops in and out (like the gauge was registering so lean it wasn't even on the chart)

Now these are like 1 maybe 2 minute bursts where no leds are light up. All the sudden it will go back to normal. (going back and forth). And then there will be another 1 or 2 min where no leds are light up.

I also noticed that while at idle, when no LEDs on the AF gauge are light up, the boost gauge shows about -15ish in HG instead of the normal -20 inHG. Also, the car randomly died at a stop today while i was lookin at the boost gauge, but started back up normal.

I will double check my connections at my ECU, because my ECU is out because I was trying to get my OBDI standalone ECU to work. All other gauges and power is ok. I soldered in my VAFC to the ECU harness, but i suppose a solder could have broke possibly?

Anyone have any idea what is going on?

Edit: Also, could my o2 sensor be going bad? I know its in somewhat bad shape due to being in and out of the downpipe and being banged around some.

 

if this only happens decelerating or at idle you're probably ok. stock o2/af gauge is only good for a range of 13-16 afr or even less. if it's doing this while under a load then i would definately be careful. after you install your wideband you will notice that your a/f will hit 20 decelerating and fluctuate from 14.5-15+ idling.

 

it seems to do this sometimes at idle, partial throttle, and full throttle, and decelerating.

Im just touchin the gas, crusin at 3K rpm or so going 30-35MPH and it can do it.

 

I would hope its one of your conections.<<Almost positive

 

Tommorow morning before i go to school, i'll check the AF gauge wire.... but the strange thing is, when i first start up the car, the gauge is ok. I even drove toward the highway. As soon as i got on the highway, it got stuck in the first red LED LEAN. I didn't even go past 4000,4500 RPM. No full throttle either, all this was done partial throttle. It wouldn't dance back and forth at all.

Until i shut it off and drove away. Weird.

Also, around 3K RPM i am sometimes get the "pop" from my exhaust (usually a sign of running too rich!) VAFC indicates that correction is a -38% while driving at this RPM.

If its not the wire, the gauge is probably fucked up or my o2 is? Should i be worried? I got a wideband that im itchin to just pop in existing o2 hole and make a quick runaround the block to see whats going on, but im superbusy the rest of the week with school, work and girls.

 

Just take it OFF!! i though it was my hondata acting strange...but it turned out to be my stupid A/F gauge!! i unplugged it and bam...damn car ran fine!! except a bit rich since my tuner couldn't figure out the problem with my car running lean so he just upped the fuel pressure as a bandage until the problem was found.

 

my buddies does this, he read the manual online and it said that it's a bad o2 sensor. His car is a 91 BTW. The manual said that if the led's go off the meter at no throttle then it's a bad o2. His is an autometer though, hope this helps ya out

 

yeah my o2 sensor is probably pooping out. it has been banged up. Thanks all

 

wait... ur a/f gauge is acting strange?! nooooo, you don't say?! this is something new