Any luck with Bluetooth OBD getting accurate IAT and Boost?

suckmyhatch

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Hey guys just curious if anyone uses and has had any luck with a Bluetooth OBD app for iOS getting accurate IAT and Boost pressure readings. I'm using OBD Fusion for reference however I'm getting wildly different readings for IAT depending on the sensor I choose. At idle after a cold start (car sits at work for 11 hours in the shade) my temps are 20-30 degrees (again depending on the sensor I chose) above ambient which seems a bit insane to me. As for boost pressure I'm reading up to 17psi??? (if i decide to go full throttle) My car is stock except for a K&N drop in. I couldn't find any info on how much boost we make stock so if anyone knows please let me know if this is right or not.

Also is heatsoak a big issue with these cars? Assuming these numbers are right, then here in NY where its been 60-70F out lately, after a bit of driving my IAT are anywhere from 100-115F. (No I'm not going full boost racing around, I have an hour commute home doing roughly the speed limit in traffic on a highway).

Anyway if anyone uses any other apps or can tell me which sensors they picked, or if using this is even worth it that would be much appreciated!

Sorry there's a lot to unpack here but I hope to get some info back, feel free to quote the parts you wanna answer!
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AFAIK... IAT is after the FMIC, IAT2 is before. For reference today in NJ it was 55F this morning. I drove to work with traffic on the parkway which was moving fairly well. I mostly stayed within 5mph of the speed limit(60-70). When I first got on the parkway my IAT was 59F and my IAT2 was 66F. When I arrived at work my IAT was 76F and my IAT2 was 90F.,

Yes heatsoak is an issue with these cars. If you get stuck in bumper-to-bumper traffic or are continually spooling the turbo the IAT's are going to creep up as the FMIC heats up.
 
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suckmyhatch

suckmyhatch

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AFAIK... IAT is after the FMIC, IAT2 is before. For reference today in NJ it was 55F this morning. I drove to work with traffic on the parkway which was moving fairly well. I mostly stayed within 5mph of the speed limit(60-70). When I first got on the parkway my IAT was 59F and my IAT2 was 66F. When I arrived at work my IAT was 76F and my IAT2 was 90F.,

Yes heatsoak is an issue with these cars. If you get stuck in bumper-to-bumper traffic or are continually spooling the turbo the IAT's are going to creep up as the FMIC heats up.
How are you monitoring your temps?
 


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suckmyhatch

suckmyhatch

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Use Ktuner or hondata. Screw that app shit. So inaccurate.
I have no plans to tune my car though, just want to monitor for fun and to have an idea whats going on with my car as well
 

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Working IAT as a custom PID:

PID: 0168
LONG NAME: Intake Air Temp
SHORT NAME: IAT
MIN VAL: -40
MAX VAL: 300
SCALE: x1
UNIT: °C
EQUATION: B-40
 

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suckmyhatch

suckmyhatch

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Working IAT as a custom PID:

PID: 0168
LONG NAME: Intake Air Temp
SHORT NAME: IAT
MIN VAL: -40
MAX VAL: 300
SCALE: x1
UNIT: °C
EQUATION: B-40
Just set this up, will report back how it works on the iOS side. I see you use Torque, I used to as well! Kind of the only thing I miss about my Android phone :/
Also, how worth it do you think the tape would be? unlike you I have an unmodified airbox
 


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It can't hurt, at least, haha.

With a completely stock setup, I still think it would be worthwhile to wrap at minimum the weird shaped intake tube that runs directly over the turbo, if not the flex tube between the MAF and that weird tube.
 
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suckmyhatch

suckmyhatch

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It can't hurt, at least, haha.

With a completely stock setup, I still think it would be worthwhile to wrap at minimum the weird shaped intake tube that runs directly over the turbo, if not the flex tube between the MAF and that weird tube.
Thanks for the answers! Planning on hitting Autozone later I'll give it a try.

Also, have you see the PRL/Mishi silicone induction hoses? Think those do anything?
 

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Thanks for the answers! Planning on hitting Autozone later I'll give it a try.

Also, have you see the PRL/Mishi silicone induction hoses? Think those do anything?
Their main function is looking nice. Yes, they will smooth out the airflow a bit, but any gains would be negligible.
 
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suckmyhatch

suckmyhatch

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Their main function is looking nice. Yes, they will smooth out the airflow a bit, but any gains would be negligible.
Yeah I know gains arent their purpose, I meant more in terms of our discussion about heatsoak
 

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Yeah I know gains arent their purpose, I meant more in terms of our discussion about heatsoak
I doubt silicon and hard plastic behave much different in terms of heat insulation, but the thickness for the hard plastic is much thinner so I would expect the silicon is less affected.
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