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Ls1 conversion, problem with O2 need some advice!

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Old Oct 24, 2013 | 04:14 PM
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Unhappy Ls1 conversion, problem with O2 need some advice!

Hey all,
Have almost finished the ls1 and 4l80 into my Aussie nissan patrol, I'm having problems with the O2 sensors, it's throwing codes and one bank is lean. The fuel system a on my efi live says ol fault, system b also says ol fault. Both the sensors are new and I've swapped them into the easy side to get to and they are fine. One bank doesn't do anything. It just sits at 450 mv. There other side when the ignition is switched on just falls to nearly zero and when it fires, jumps up to 850-900 mv. One thing I noticed is that they wouldn't do anything if just hooked up but out of the extractors , is that normal, thinking earthing
I pulled the loom up into the engine bay to check the loom, and both sides have power and earth and the sensor high and low have continuity back to the ecu plug.
Ive also sprayed all round the intake with throttle body cleaner and the vacuum pipes and the motor doesn't stir. I had changed the intake o rings, but everything was clean and spotless when assembled. I even changed the Pcv valve.
It almost feels like I've missed a wire somewhere but everything is connected to where it needs to be. Have been over heaps of wiring diagrams, the yank ones and the Aussie ones and am stumped. I did check the general condition of the earths around the place and the ones to the body were giving me a lil bit of resistance, I'll renew them tom and get it down to as little as possible.
Do you guys have any ideas?
The extractor gaskets are new, and no sign of leakage, was going to pull them and run a lil bit of silicone on them just to def rule out an exhaust leak.
Cheers in advance
Karl
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Old Oct 24, 2013 | 06:19 PM
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If the sensor voltage is steady 450 then it is most likely the sensor or wiring. Double check the wiring again since the sensors are new. Also, make sure you don't have a broke pin on the pcm.
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Old Oct 25, 2013 | 06:22 PM
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I will double check today, I'm also redoing all my earths to get the ohms to as low as I can, going to extend the wires as they are tight over the transmission.
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Old Oct 27, 2013 | 05:01 PM
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Redid the earths, extended looms, checked wiring and now one sensor trails the other. I can't get it to run right in closed loop, so for the minute it's in open loop. I think I had a broken/faulty wire one the coil cradle. It would plat up ,then give the connector a bit of a wiggle and it would clean up. That whole side of the engine is a lot cooler. Pipes are cooler and the injectors don't seem to have a real solid click as the other side. If I disable the individual cylinders, that bank doesn't have as big effect as the other.
Or I buy 2 new sensors and put it back in closed loop enabled and see what happens. Just good to be able to drive it!
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