code 34 troubles

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sjbsuperman1425
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Well I just got my engine back together and what not. Now im having a knock sensor code 34 fight with me. Never had it before now. I did have to repair the connector because it broke off at the wire when i was initially hooking everything up. It has continuity at the connector as well. I tried changing the knock sensor and still throws code 34 right after start up. Any ideas?

Thanks guys

Zak


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float_6969
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As an experiment, try running a new wire from that pin on the ECU (don't know which one it is with out opening up the FSM and looking) to the knock sensor and see if it goes away. I've found the ECU is much more sensitive to a poor connection than a multimeter is.

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sjbsuperman1425
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I unplugged the ECU from the harness and have continuity between the ECU connector and the knock sensor connector. I just talked with a buddy of mine and since I repair the broken knock sensor wire I had to open up the shielded wire to be able to fix the break. He suggest that the shielded wire may be touching the signal wire somehow and causing the short. So I think tonight I'm going to go back at it and remove the "extra" shielding that I half assed removed when I fixed it to see if that is the case. I guess it is really the only variable that changed from last year to this year since I had nistune all last year with the same harness and knock sensor and never had an issue.

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sjbsuperman1425
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FIXED!!

When I originally repaired the knock sensor connector, I must have forgotten or to heat shrink one of the solders and just wrapped the wire in electrical tape. Turns out the wires in the shielding were touching the knock sensor signal wire and grounding out causing the dreaded Code 34. I re-repaired the wire and Code 34 no longer appears on my ECU Message screen in Nistune. All fixed!

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float_6969
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woot!

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sjbsuperman1425
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for everyone that is familiar with tuning and all, does anyone have any idea what would cause my ECU to jump to knock maps on startup? I do have solid motor mounts and no Codes in the ECU and am running NIStune, but I cannot think of anything any reason why it would just automatically jump to knock maps.

boost_boy
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Are you sure the knock circuitry isn't damaged in your ecu? Or if you have another known working ecu, give it a go and see what happens.

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sjbsuperman1425
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I'm assuming the ecu is fine because it worked fine last year and literally sat in my car in the garage all winter. I do not have a spare either. Also after I fixed the knock sensor code a few weeks ago it was reading the correct maps. Nistune does pick up 1 knock count on start up as well but not sure what would cause that.

boost_boy
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Just throwing it out there at you, man. For the last 3 years, my 2002 Nissan Maxima has been giving me a code P0011/P0021 even after I rebuilt the engine, changed IVT solenoids, changed cam and crank position sensors and all kind of crazy stuff, but the codes will always come back. Finally got fed-up with the crap performance of my car and opened-up the ecu and "Voila" a burned trace. Replaced it with a similar computer from another maxima along with the security device and key needed to make the computer active and no more code P0011/P0021. I would've never known had I not decided to open the ecu to be nosy. That may not be your case, but it wouldn't hurt to inspect for peace of mind as well.

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sjbsuperman1425
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I opened it up when I originally had this Code 34 issue and everything looked pretty clean and tidy. I do hear some kind of knock or clunk on start up sometimes but its not all the time and when listening with a screw driving on the engine/oil pan and stuff I hear nothing but good noises. I'll have to dig into it this weekend because I have no idea whats going on..


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