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ibsorgn
07-22-2012, 02:49 PM
I have a question I thought that I would pass it by this forum. I'm now running a 1st gen TT ECU in my 94 supercharged SL but I recently have noticed the AF ratios have been bouncing around a lot. Using Pin#7 and ground on the ODB1 hybrid, I got two signals 11 and 39 which indicates that the ECU is not receiving o2 signals. (I split my single O2 signal and feed both O2 pins #55 and #56). So I thought, no big problem, I'll just replace the O2 sensor. No change, so I decided to take a closer look and found that I'm getting power to the O2 heater, Ohms test shows continuity to the O2 signal & heater ground but no pulsating voltage for the o2 signal wire. In fact when I rev the engine I get a momentary increase in the O2 signal voltage then back to zero. Can you suggest what I might test or what might be the problem? I'm stumped!
ibsorgn
10-28-2012, 06:50 PM
I have a question I thought that I would pass it by this forum. I'm now running a 1st gen TT ECU in my 94 supercharged SL but I recently have noticed the AF ratios have been bouncing around a lot. Using Pin#7 and ground on the ODB1 hybrid, I got two signals 11 and 39 which indicates that the ECU is not receiving o2 signals. (I split my single O2 signal and feed both O2 pins #55 and #56). So I thought, no big problem, I'll just replace the O2 sensor. No change, so I decided to take a closer look and found that I'm getting power to the O2 heater, Ohms test shows continuity to the O2 signal & heater ground but no pulsating voltage for the o2 signal wire. In fact when I rev the engine I get a momentary increase in the O2 signal voltage then back to zero. Can you suggest what I might test or what might be the problem? I'm stumped!

<<<<<<<<<<<<Solved>>>>>>>>>>>>
DocWalt
10-29-2012, 10:07 AM
What was the issue? I'm sure someone else will run into this down the line.
ibsorgn
11-01-2012, 09:26 AM
What was the issue? I'm sure someone else will run into this down the line.

The replaced O2 was defective. Returned it and replaced with another and all is fine.
DocWalt
11-01-2012, 12:47 PM
Ok, glad to hear it was something simple.
ibsorgn
11-05-2012, 06:13 PM
Ok, glad to hear it was something simple.

My last guess was a defective NEW O2 sensor! But it does happen - Live and learn.