Hey everyone,

I am getting code 42 on the ECU,

Where can I find the fuel Temperature sensor?

What would a malfunctioning sensor cause?

Thanks!

Mounted on the fuel rail, on the driver's side, as I recall. Just a bad electrical connection maybe?

http://www.courtesyparts.com/3....html

Part number 22630W and not sure if the plenum needs to be removed to access it. A malfunctioning fuel temperature sensor might affect performance and mileage.

Thanks Gerry,

I am going to look into this later today and ill post an update,

Thanks for the help

well it looks like I am getting just about 15MPG and I have noticed sluggish performance.

I'm going to see if i can pull the sensor out with out removing the plenum.

Do you know what voltage the sensor should be receiving?

Check the FSM to see if there's anything about testing the sender unit or the wiring from it to the ECM? Might was well have a new one on-hand too, if it turns out the unit itself is bad and you will be removing it.

http://www.autoshop101.com/forms/h32.pdf

Have you searched fuel temperature sensor problems? Good luck with yours.
Modified by GerryO at 4:06 PM 10/14/2009

you should be able to get it out without removing plenum. only thing you might wanna do first is to bleed the pressure out of the system by pulling a fuel line or you will have a geyser of fuel spraying under the hood.

i can get a pic in a little bit of its location

i also use this to do work on the J30. not all the same parts but for the motor and some other components it helps out a lot.

http://www.300zx-twinturbo.com/cgi-bin/manual.cgi

Here is a pic with arrow pointing to the sensor. looks liek you can use a deep well 12mm socket to take it out.



Its next to the #2 injector which is on the drivers side of the plenum.

I get all my motor parts from these guys: http://www.z1motorsports.com/p...=1731

Much appreciated swimshark, Ill test the circuit on it today and order a new one to put in, deep socket should work. I still cant seem to find anything on the correct resistance and voltage output, but ill post up my values.

Ill keep you all posted

http://www.300zx-twinturbo.com...l=133

This shows that for the thermal transistor at 140 degrees it should be 70-90 ohms. I know from watching my levels with my Scan Tech Nissan program that when the J is at its hottest sitting at idle that fuel temp can get up to about 127 or so. With most normal cruising up to about 108 during this time of year.

On the manual it says for 212 degrees it will read a lower ohmage so for around 108-120 degrees I would guesstimate around or above 100 ohms when you test it at running temp.

Hey is there any way you could take a zoomed out picture? I cannot seem to be able to find the sensor!

Thanks a ton,

Andy

Well, I found the spot where it screws in... the only problem is that there was nothing there to begin with heh. and there is no wire visible anywhere that would be the correct connection to the sensor. I guess the previous owner removed the unit all together, so does anybody know how I can re-install this wire?

Thanks for all your help everyone.

would you be able to take a picture of the same area? did you check the harness near the injector and coil pack plugs on the harness? that would be really odd is they removed the whole sensor and harness.

Sure, I will take a picture tomorrow but I looked all around and found no loose wires/connectors at all. It is very strange but hopefully i can splice in a new wire and connector.

well you need to find the wires to the pre existing temp sensor. this goes directly to the ECU. to successfully rewire it in you would have to find out which pin is for fuel temp on the ECU connector and run that wire out into the engine bay if you cannot locate it.

I had the exact same problem. I bought a new sensor, mounted it in the open spot.

From what I can find it should go to the white wire on the bottom of the brown plug marked f8 in the FSM.

When I test the voltage getting to the sensor I only read 3.7v instead of the 5v that it should be reading?

I'm going to take it for a drive & report back with pics of my engine compartment.