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Discussion Starter #1
I installed a new wideband air/fuel sensor and gauge on my 83' GTV6 to try and find out why it's running so lean (plugs are WHITE and it pings at high rpm when warm). I am unable to get the gauge to stay anywhere except 7.4 (where it starts measuring) or 22.5 where it stops. Based on what I have read, I should be metering between 14 and 15 when idling. I have tried to adjust the AFM while idling to get it to read in that zone but am unable to stop the values from jumping all over the place. It only blips between these 2 values momentarily under load and acceleration. What can I check next? I have checked all of the common problems eg:vacuum leaks, unmetered air etc. O2 sensor is new, fuel pump is new, coolant temp sensor is new....it runs well except when warm. What in the hell am I missing? Is this injectors? or? Any help would be appreciated.
 

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But Mad North-Northwest
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L-jetronic averages 14.7 but continuously oscillates from rich to lean. Maybe that's screwing up your AFR meter? What does the voltage output of the stock O2 sensor look like?

Have you checked fuel pressure? A bad fuel pressure regulator can cause lean running.
 

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Discussion Starter #3
L-jetronic averages 14.7 but continuously oscillates from rich to lean. Maybe that's screwing up your AFR meter? What does the voltage output of the stock O2 sensor look like?

Have you checked fuel pressure? A bad fuel pressure regulator can cause lean running.
Have not checked either. Fuel pressure regulator is new as is 02 sensor. What am I looking for in those two outputs? I can give it a try, Thanks!
 

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Where is the A/F meter's sensor installed?

The original O2 sensor should output between 0.1 & 0.9V once warmed up. Leave it connected to the car's wire harness - pull back the rubber boot and connect the red probe to the O2 sensor & black probe to ground. Use a digital voltmeter. If the L-jet computer is doing its job, the readings should vary but average out to about 0.45V.
 

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When you installed the wideband what did you do about the narrowband signal for the ECU that was coming from the old probe? Did you install a new bung for the wideband sensor or did you replace the narrowband with the wideband?. I have a Zeitronix ZT-3 in my GTV6 and it has a simulated narrow band output that goes to the ECU. The wideband is pretty steady and does not jump around or oscillate between rich and lean.
 

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Discussion Starter #6
I had a separate bung welded in. I called Innovate and they suspected that the sensor needed to be recalibrated so I did and it seems to be working as intended. Now I can actually focus on the problem. Thanks guys for the response. I am almost certain I will be back!
 
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