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Hey guys, with minimal tools, is there a way to thread the Haltech IAT sensor at the OEM location or somewhere else easy ?

I bought this sensor and going for a tune with the Haltech ecu this week-end. However, I still havent figured if I will be able to use my Haltech sensor or not.

thanks!

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https://www.sau.com.au/forums/topic/442832-haltech-iat-vs-oem-iat-rb26/
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Might be off topic, but what's wrong with the stock IAT? it already is connected on the harness and goes to the ECU, I'm sure the Haltech reads it.. unless you're not running a Plug In one.

Might be off topic, but what's wrong with the stock IAT? it already is connected on the harness and goes to the ECU, I'm sure the Haltech reads it.. unless you're not running a Plug In one.

There's plenty wrong with it. It is a big heavy lump - essentially the same as the coolant sensor. It is seriously affected by the temperature of the plenum itself (rather than the air flowing through it). The Nissan ECU doesn't really use it for the same reasons that other ECUs use IAT sensors. If you're MAP sensing then you have to measure IAT in order to get the density calculation right. But the Nissan ECU was using a MAF, so it had no need to measure IAT. The general concensus is that the Nissan ECU only uses the air temp for taking action in case of severe high temperature.

There's plenty wrong with it. It is a big heavy lump - essentially the same as the coolant sensor. It is seriously affected by the temperature of the plenum itself (rather than the air flowing through it). The Nissan ECU doesn't really use it for the same reasons that other ECUs use IAT sensors. If you're MAP sensing then you have to measure IAT in order to get the density calculation right. But the Nissan ECU was using a MAF, so it had no need to measure IAT. The general concensus is that the Nissan ECU only uses the air temp for taking action in case of severe high temperature.

Correct, it's junk... I use mine but I really should get off my ass and install a adequate high speed air temp sensor

There's plenty wrong with it. It is a big heavy lump - essentially the same as the coolant sensor. It is seriously affected by the temperature of the plenum itself (rather than the air flowing through it). The Nissan ECU doesn't really use it for the same reasons that other ECUs use IAT sensors. If you're MAP sensing then you have to measure IAT in order to get the density calculation right. But the Nissan ECU was using a MAF, so it had no need to measure IAT. The general concensus is that the Nissan ECU only uses the air temp for taking action in case of severe high temperature.

makes sense, I never thought of it that way :)

I've got mine welded to my cross over Plazmaman pipe before the TB (I deleted the the fugly stock RB25DET cross over pipe)

  • 6 years later...

Question. 

Would you need to have the car retuned if using a plug n play fast air temp sensor? 

Like the below?

https://www.dahtoneracing.com/online-store/Dahtone-Racing-RB26-plug-and-play-fast-response-IAT-sensor-p200603263

Having a Haltech CAN gauge vs MFD intercooler sensors on the 34R, i notice an approx 25-30 degree difference between the IAT sensor vs Intercooler sensor (Intercooler reads 30 odd degrees vs 50-60Deg on the IAT)

Since the Haltech has been tuned to drop timing etc on air temp, i'm certainly feeling a drop in power due to heat soak of the IAT. 

 

Edited by djvoodoo
On 28/12/2020 at 8:13 AM, djvoodoo said:

Would you need to have the car retuned if using a plug n play fast air temp sensor? 

Not at all, just get a GM or Haltech sensor. Go into your ECU, hit F4 then select the IAT sensor, select the correct scaling (haltech has a bunch of calibration files ready to go), save, and done!

 

(also, I would just cut the plug and re-terminate instead of using an adaptor which over time may corrode, snap, etc. and increase resistance over time)

  • 3 years later...
48 minutes ago, GTSBoy said:

Well, you'd have to. The non-26 RBs do not have IAT sensors anywhere else that you could replace if you wanted to.

Do you have to, though? That sounds quite messy to me. Surely it would be easier to place it a bit further down. And drill into easily replaced piping instead. See the old replies above as well.

FWIW the Blitz intercooler kit on my RB25 has a nipple on the elbow of the pipe going into the plenum. No need for drilling. Looks vaguely like this:

icse_kit.thumb.jpg.8b812b1f0af04400a6217b480d96ede2.jpg

Well, it is trivial to drill a hole and tap a thread into the thick cast alloy of the cross pipe. It is not possible to drill and tap/screw a fitting into thinwall steel or alloy pipe. You need to weld something on. So, yeah, if I was doing it, I would throw it in that pipe somewhere.

As to that Blitz kit's already welded in fitting....well, that's what it's there for, and that's essentially the same place, give or take.

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