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I know there is a sensor that controls fuel on my rb26 according to temperature, does anyone know how I can test the one I have now, and where can I buy a new one.

I have a power fc and was also wondering if I can use that to see if the sensor is good or not.

Thanks.

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Coolant temperature sensor. Do some googling for the expected resistance vs temperature. Test it in hot water on the stove with a thermometer (at one cold temperature and one hot temperature) and see if it lines up with the spec.

You can buy a new one from Nissan, eBay, about 30 trillion on-line retailers, etc.

Edited by GTSBoy
  On 17/06/2014 at 9:25 PM, blind_elk said:

Don't RB26s run an air temp sensor to measure how hot the air going into the engine is? I would put that one ahead of the coolant sensor.

Pretty sure you will find that would actually have far less of an effect on the fuel ratio.

Edit.

Actually I'm not sure the ecu even uses it.

Edited by Ben C34

I pulled my plugs and seem like its running rich. And at one point it was hard to start. Once started it runs fine. Looking at idle my afr gauge was around 12s. I would have to go into my power fc and manually pull fuel out to get it to read around 14s or less. Im still waiting on some parts to reach then ill test and tune things. I have a strong feeling that my temp sensor is acting up.

  On 17/06/2014 at 10:34 PM, GTSBoy said:

The ECU uses it, but as far as I can tell, not for anything in the day to day setting of mixtures or timing. I think it is only there to call a halt to proceedings if temperatures get way too hot.

i think it uses it to pull ign timing when inlet temps get too high....i'll double check though.

Edited by Badgaz

looks like it'll do both, however it is inj vs airT and boost. which i'm guessing might only be enabled if you have the PFC boost control kit. 50 degree airt = 0 60 degree airt = 3 degrees retard 70 degree airt = 5 degrees retard

  On 18/06/2014 at 9:34 AM, MJTru said:

I pulled my plugs and seem like its running rich. And at one point it was hard to start. Once started it runs fine. Looking at idle my afr gauge was around 12s. I would have to go into my power fc and manually pull fuel out to get it to read around 14s or less. Im still waiting on some parts to reach then ill test and tune things. I have a strong feeling that my temp sensor is acting up.

i think i have this same problem with my wifes GTR...the temp never went over 75 on a night of logging and tuning which meant it was always getting slightly more fuel across the whole map.

  On 18/06/2014 at 10:15 AM, Badgaz said:

looks like it'll do both, however it is inj vs airT and boost. which i'm guessing might only be enabled if you have the PFC boost control kit. 50 degree airt = 0 60 degree airt = 3 degrees retard 70 degree airt = 5 degrees retard

Doesn't really matter what the PFC does with it....it matters what the factory ECU does with it. Which isn't much.

Face it, about the only Nissan engines that have the air temp sensor are the RB26 and the SR20. And the sensor is a big lumpy slow reacting piece of crap better suited to measuring coolant, so it's hardly going to be used for serious business. That's why we have air flow meters.

  • Like 1
  On 18/06/2014 at 12:22 PM, GTSBoy said:

Doesn't really matter what the PFC does with it....it matters what the factory ECU does with it. Which isn't much.

its much colder here in NZ. it was about 8 degrees that night. it matters to me what the PFC does to it....and i don't care what the Factory ECU does, but i'll find out anyway...and i think the OP has a PFC. Just checked my logs and water temp was sitting 75 degrees to 77 the whole time...the IAT was showing 30 degrees....

Badgaz, GTSBoy was referring to the air temp sensor, not the coolant temp.

It sounds like your wife's car might have a low temp thermostat installed. Which sucks. Alternatively you could look online and fine the resistance at various temps for the coolant temp sensor and test it with a meter. I would do that before pulling out the thermostat.

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