zl1 weird temp sensor issues and questions - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

madmikeismad · 05-11-2020, 02:19 PM

'12 zl1, using hp tuners

So I've been logging ever PID that gives a reading, just for fun. My IAT chart was super jagged, and doing funky things, like changing the numbers in the log after the run stopped and autosaved. I fixed that by deleting "intake air temp 2" from the sensor list. Now the chart is a smooth line that matches up with "intake air temp", mostly.

Screenshot 1 is while logging, 2 is after the log ends and autosaves. 3 is showing the difference between the sensor list readings and the chart.

Now for the questions.
What exactly is "intake air temp 2"? To my knowledge that isn't actually a sensor
What exactly is "manifold air temp"? I'm not aware of that being a sensor either, but this is my first lsa so I'm not sure if there's a sensor behind the lid or something.
Are these maybe temp sensors that are part of another sensor, like how the standard IAT is read at the MAF?
EDIT: it appears that intake air temp 2 might be a filtered reading of manifold air temp, or vice versa. So that explains that

Which sensor reading is actually used to retard timing? I started this endeavour after it started pulling 8-11* of timing at WOT.

madmikeismad · 05-11-2020, 02:43 PM

So I googled the crap out of it, and found a very old post from chris at HP tuners. It seems iat2 is used for timing. So if that's the case, then it directly matches the iat spark tables and the timing I'm losing. Guess I'm pulling my lid now.

fleebag · 05-22-2020, 07:23 PM

I've always had an issue with the IAT's and the Ambient sensor.

IAT(sae) I think has correct readings as it goes down when I use Alky

IAT2 is stuck on 32* never changes.

Ambient sensor only shows 32 to 50* or so. BUT... the Ambient display in the radio show correct outside temp????

Now from your comment on HPtuners post stating IAT2 readings is used for timing??

madmikeismad · 06-07-2020, 08:00 PM

Quote:

Originally Posted by fleebag

I've always had an issue with the IAT's and the Ambient sensor.

IAT(sae) I think has correct readings as it goes down when I use Alky

IAT2 is stuck on 32* never changes.

Ambient sensor only shows 32 to 50* or so. BUT... the Ambient display in the radio show correct outside temp????

Now from your comment on HPtuners post stating IAT2 readings is used for timing??

Blower cars used iat2, n/a cars used iat

05-11-2020, 02:19 PM	#1
madmikeismad Drives: 2012 ZL1 Join Date: Mar 2020 Location: Oklahoma City Posts: 66	zl1 weird temp sensor issues and questions '12 zl1, using hp tuners So I've been logging ever PID that gives a reading, just for fun. My IAT chart was super jagged, and doing funky things, like changing the numbers in the log after the run stopped and autosaved. I fixed that by deleting "intake air temp 2" from the sensor list. Now the chart is a smooth line that matches up with "intake air temp", mostly. Screenshot 1 is while logging, 2 is after the log ends and autosaves. 3 is showing the difference between the sensor list readings and the chart. Now for the questions. What exactly is "intake air temp 2"? To my knowledge that isn't actually a sensor What exactly is "manifold air temp"? I'm not aware of that being a sensor either, but this is my first lsa so I'm not sure if there's a sensor behind the lid or something. Are these maybe temp sensors that are part of another sensor, like how the standard IAT is read at the MAF? EDIT: it appears that intake air temp 2 might be a filtered reading of manifold air temp, or vice versa. So that explains that Which sensor reading is actually used to retard timing? I started this endeavour after it started pulling 8-11* of timing at WOT. Attached Images

05-11-2020, 02:43 PM	#2
madmikeismad Drives: 2012 ZL1 Join Date: Mar 2020 Location: Oklahoma City Posts: 66	So I googled the crap out of it, and found a very old post from chris at HP tuners. It seems iat2 is used for timing. So if that's the case, then it directly matches the iat spark tables and the timing I'm losing. Guess I'm pulling my lid now.

05-22-2020, 07:23 PM	#3
fleebag Drives: Moneypit Join Date: Nov 2013 Location: Jax FL Posts: 163	I've always had an issue with the IAT's and the Ambient sensor. IAT(sae) I think has correct readings as it goes down when I use Alky IAT2 is stuck on 32* never changes. Ambient sensor only shows 32 to 50* or so. BUT... the Ambient display in the radio show correct outside temp???? Now from your comment on HPtuners post stating IAT2 readings is used for timing??