Error codes 42 and 34 - Knock sensor and Fuel Temp

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Ace2cool
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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby Ace2cool » Mon Feb 18, 2013 8:57 pm

IAmAlive wrote: so I should just pull the floorboard and check the pins on the ecu connector for the brown wire?
Yes. Pull the connector off the ECU, get a meter, and read resistance between the severed end of the brown wire and pin #36 on the ECU connector. Don't just hook stuff up without checking where it goes to. You can seriously damage stuff if you do that.

Also, you're positive the black wire goes to the fuel temp sensor? Electrical errors can be very hard to fix and very costly.


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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby IAmAlive » Mon Feb 18, 2013 9:18 pm

The black wire does go directly to the sensor. It's very short and I traced it to the sensor easily, because it was zip tied around all the other wires that were wrapped up.

I'll give an update when I test the pins tomorrow thanks for the help!

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby Ace2cool » Mon Feb 18, 2013 9:21 pm

No problem dude. That's what we're here for.

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby IAmAlive » Wed Feb 20, 2013 5:23 pm

So I pull the ecu, pull the connector, and instant derpbrain. I counted the pins to the one marked 36 on your diagram and saw the brown one wrapped in black. And my guess is that is the one I'm looking for. Other than that, sad to say, but I'm lost. Image

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby Ace2cool » Wed Feb 20, 2013 5:38 pm

Where does that go? Did you read it with a meter?

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby IAmAlive » Thu Feb 21, 2013 10:19 am

Alright. So i figured out that brown wire was the one meant to go to the fuel temp sensor. I opened up the tape holding all the wires by the coils and injectors, and tested that brown wire from there and at the ecu connector. Voila, turns out that's the one, and that black wire connected to the fuel temp sensor had been spliced in by the previous owner.

So crimped a butt connector on those wires, rewrapped it with the other wires and I believe that's all. Now I have to clear the codes. Just remove the battery terminals for a few hours i believe?

Knock sensor relocation is the next weekend project to take care of. :rolleyes:

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby t.mcginley.jr » Thu Feb 21, 2013 10:35 am

When you follow this procedure to check the codes:

http://www.nicoclub.com/archives/nissan ... ostic.html

Cycling between Mode 1 (normal) and Mode 2 (code checking) two times will clear the codes.

The KS relocation should be much easier to do, where did you decide to relocate it to?

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby IAmAlive » Thu Feb 21, 2013 10:54 am

Sweet thanks man.

And I haven't really decided yet. Suggestion?

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby t.mcginley.jr » Thu Feb 21, 2013 11:09 am

I relocated mine to the rear plenum bolt. There are 8 bolts (I think?) holding the upper plenum to the lower intake, I used the furthest back drivers side one. It looks like this (not my pics, but same thing):

Image

Image

That way the KS is easily accessible and still bolted to the lower intake, which is closer to the block than just bolting it to the upper plenum.

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Re: Error codes 42 and 34 - Knock sensor and Fuel Temp

Postby t.mcginley.jr » Thu Feb 21, 2013 11:10 am

The pics are from this article if you didn't already see/read it:

http://www.twinturbo.net/nissan/300zx/f ... ation.html


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