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6 hours ago, TXSquirrel said:

Is Greddy or HPI intercooler no good?  With shipping to the States, they will cost less than Plazmaman for me.

My car has a HPI Aluminium Radiator. It did the job on a super hot tack day (38 degrees).

I can't comment too much, but it seems to do the job. You should probably value the opinions of the others over me though... they've been around a while longer than me.

  • Like 1
18 minutes ago, Hadouken said:

^^ especially, seeing as the topic is intercoolers...

Damn it! Well, i proved my own point, i guess.

I don't know what intercooler I have, guess i will have something to look at tonight.

Edit: ok, having acheived peak stupid today, i'm going to log off and go have a nap.

Edited by Steve85
  • Like 1

I am reading this post because my bnr32 is having high IAT issue.  

During normal driving when ambient temp is below 30C°, my coolant temp would stay between 75C°-80C° as I have Nismo's lower temp thermostat.  However the IAT is consistently showing above 50C°.  If I'm idling for a while in stop-go traffic, the IAT would creep pass 55C° while coolant still staying below 80C°.

Is that normal?  Is my factory intercooler not working properly?  Or there are other issues at play?  I figure it couldn't be the fan or fan clutch because coolant temp reads just fine.

Car is still all factory, down to the air box.  

 

The IAT sensor currently in the car is a brand new Nissan OEM.  My first thought was a bad sensor so I bought a new one, but reading is the same.  

The new sensor looks completely different tho, it's a much thinner rod and the plug is blue instead of yellow.  To make sure I got the correct part I even tested both new and old sensors in hot water to see if the ohm readings are in range, which is probably what I should have done before I went and bought a new one...

I also notice my car smells quite rich, but I'm not sure if it's because I have a straight pipe or the ECU is compensating for high IAT readings.  However as far as I can tell the lambda readings off the factory narrow band are normal.  Unless the Greddy Infometer I'm using is getting every reading wrong...?

So your readings are coming from the Infometer?

You said that you checked the sensor using water before - could be worthwhile checking the resistance output of the sensor using a multimeter hooked up during running to confirm that its not the Greddy being a bit optimistic.

Are you using a stock ECU?

Edited by baron_von_bootsector
forgot the ecu question

He already checked the resistance he said. 

Where abouts is the sensor located. 

If the Greddy is the only way you can read that data, my guess is the calibration is wrong. 

The car would drive like shit with 50deg intake temps/

7 minutes ago, ActionDan said:

He already checked the resistance he said. 

Where abouts is the sensor located. 

If the Greddy is the only way you can read that data, my guess is the calibration is wrong. 

The car would drive like shit with 50deg intake temps/

Yep thats what I was getting at, check the output of the sensor while its on the road to confirm the Greddy is not the issue. A few feet of wire and some alligator clips and you are set.

Edited by baron_von_bootsector

Everything is stock in the engine bay and so is the ECU.  The IAT sensor is still at its factory location on intake plenum, at the kink before first throttle body.

Infometer is pretty much a plug-n-play off factory consult port, only the AFM and O2 voltage can be adjusted/calibrated.

I have swapped around the sensors a couple times with the factory radiator one and a 2nd new OEM one (yeah I bought another one just to be triple sure :(), same result...

4sensors_50.jpg.35f2ebd86e8c0b7f7855f630d5ee5812.jpg

At least car doesn't drive like shit, I think... well, this is the only bnr32 I have ever driven...  So I do hope Infometer is showing false readings, because I don't want to drop $650 USD for a new intercooler when the factory unit is working fine.

Factory core good for 300rwkw+ without issue at all.

Might be time to extend/alligator clips and do some more testing in other locations/outside engine bay etc.

Any Nissan dealerships around you/import shops that might have a proper consult so you can get a readout from the ECU?

You cold also buy a consult cable and use ECUTalk (which I think was free). 



 

The RB26 IAT sensor is not really doing a good job of measuring the air temperature.  It really reflects the plenum temperature, which is often a lot hotter than the air.  For this reason, the RB26 ECU doesn't look at the IAT for any normal fuel-air or timing input.  It's really only there for the ECU to go into a panic if it get seriously hot.

So before getting too worried about the IAT sensor, the infometer, or anything else, I'd suggest slipping a skinny wired thermocouple bead under a hose clamp after the intercooler and try to measure the air temperature more directly.  Or install a proper IAT if you want to go banzai on it.

Without wishing to go OT, how is it that the RB26 IAT sensor measures plenum temp rather than air temp? Doesn't that suggest that no matter where and IAT it is it'll measure the temp of the thing in which it's sitting rather than the air? What does the RB26 ECU use for normal fuel-air or timing input?

Because it hardly protrudes into the airflow at all and isn't insulated from the plenum at all so just heart soaks as the plenum temp increases. Yes it will rise with IAT but won't be very responsive at all. ECU will use AFM, O2, Knock and coolant temp to calculate fuel injection from memory.

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