I'm having a heck of a time troubleshooting an issue keeping my 96 FZJ80 from passing smog, and I'm hoping the braintrust on Mud can help me out with some diagnostic data.
Does anyone have a graph showing good downstream O2 sensor data (at temp), preferably both idle and up in the 2k+ rpm range?
I'm not sure if I should be seeing a steady wave or a fixed stable value (around or above?) 450mV. If it's a wave, should it be crossing the 450mV mark, by how much, and how often?
I'm seeing a somewhat steady wave between ~375-525mV, cycling about once per second.
My upstream O2 is outputting a similar frequency, but of course it's got a higher amplitude, at ~200-800mV.
Reading around online about the narrow band sensors, it seems the downstream is supposed to cross the 450mV mark once per second, or maybe 3 times per second, or maybe never and just float above it around 600mV. I honestly don't know how to verify which is correct without someone with a working system confirming.
I'm not looking for a complete solution yet - just some data to help me diagnose further. If anyone can help, I'd really, really appreciate it. I've got a trip coming up in a couple days and I really need this sucker to have passed the smog test before I leave.
As a side note, I'm in California, so all CARB compliant parts (like a new pair of cats) are plenty expensive.
Does anyone have a graph showing good downstream O2 sensor data (at temp), preferably both idle and up in the 2k+ rpm range?
I'm not sure if I should be seeing a steady wave or a fixed stable value (around or above?) 450mV. If it's a wave, should it be crossing the 450mV mark, by how much, and how often?
I'm seeing a somewhat steady wave between ~375-525mV, cycling about once per second.
My upstream O2 is outputting a similar frequency, but of course it's got a higher amplitude, at ~200-800mV.
Reading around online about the narrow band sensors, it seems the downstream is supposed to cross the 450mV mark once per second, or maybe 3 times per second, or maybe never and just float above it around 600mV. I honestly don't know how to verify which is correct without someone with a working system confirming.
I'm not looking for a complete solution yet - just some data to help me diagnose further. If anyone can help, I'd really, really appreciate it. I've got a trip coming up in a couple days and I really need this sucker to have passed the smog test before I leave.
As a side note, I'm in California, so all CARB compliant parts (like a new pair of cats) are plenty expensive.
