A/F ratio gauge on 96 3100

[Jbrogan]

Ok i put and auto meter narrow band A/F ratio gauge on my 96 beretta 3100. i hooked it to the purple wire of the o2 sensor. What happens is interesting. when you start the car, regardless if the engine is warm or not, the gauge reads lean for five minutes and dosent bounce like its suppose to. then after the five minutes it starts bounce stoich like it suppose to. now, if i drive the car in those fist five minutes the idle is up and down, it stalls, and it spudders when you are going. When the gauge is bouncing after five minutes if you drive it the gauge works and the car runs fine. now does anyone know wtf is going on here???

[sprucegagt]

Did you splice into the O2 wire or just cut it off and connect straight to it?

[Jbrogan]

i spliced it in, i cut the purple wire in half and the hooked the a/f ratio gauge wire in with both the halves so 3 wires go into a wire nut. yes the pruple wire stil has a connection from the o2 sensor to the ecu.

[sprucegagt]

Then you may of damaged the heater circuit in the O2 sensor. Did the car sputter and stall before installing the gauge?

[3400-95-Modified]

A wire nut??

Wow get that out of there and solder the connection in with heat shrink.

[ForcedFirebird]

A wire nut??

Wow get that out of there and solder the connection in with heat shrink.

Easier said than done, the o2 wire on my car wouldn't solder. The stock o2 is gone and replaced with a LC-1 anyways. My friend who solders electronics for a living said it was a special composition wire to resist heat.

[3400-95-Modified]

Ok then crimp it with a crimp connector, just not a wire nut... this isn't an "electrical" job, its electronics... two totally different things. Worse case use one of those wire taps, Thats what I'm using... its better than a wire nut. And you could also tap the harness and solder it in, if the sensor itself has special wire.

[ForcedFirebird]

Ok then crimp it with a crimp connector, just not a wire nut... this isn't an "electrical" job, its electronics... two totally different things. Worse case use one of those wire taps, Thats what I'm using... its better than a wire nut. And you could also tap the harness and solder it in, if the sensor itself has special wire.

Yeah, I am unsure if the wire is the same beyond the connector that goes to the harness. I used a tap the first time, it worked fine.

[Jbrogan]

ok, if the a/f ratio gauge wire is hooked up with the o2 wire (still hooked to ecu) it spudders at first and after 5 min it runs fine. if i unhook the a/f gauge and reconnect the o2 wire (with the wire nut) its perfectly fine.

[ForcedFirebird]

Do you have the AFR guage grounded in the same place as the ECM (recommended)?

[Daguse5853Z]

A wire nut??

Wow get that out of there and solder the connection in with heat shrink.

A wire nut?? LOL that is amazing. if you don't at least crimp it and put heat shrink on it you are just asking for problems later on. corrosion etc that could be your problem right there, bad connection, or not.

[3400-95-Modified]

Mines not grounded in the same place as the ECM and it runs fine, I bet the gauge signal wire is grounded somewhere causing a short.

[Jbrogan]

well it just started working right so idk i guess if it Fs up again ill post it

[IsaacHayes]

Sounds like you've got a short or a break in the wiring. Solder or crimp everything up and use heatshrink with electrical tape over that to protect from water and corrosion. You don't want to be driving and then end up with a problem in the middle of no where.