Cascade Crew

MrMike98 · Member Joined: 18 May 2010 Posts: 231 Location: Bremerton

moving the air inlet/manifold air temp sensor from under plenum to inlet ducting.
i am replacing the plenum so now would be a good time...

mechanically simple-unscrew from plenum-plug plenum-extent/reroute wiring harness-mount sensor in inlet duct near TB.

questions:/?

do i use same sensor-is there a better one??

any changes to the ecm bin file needed? i can edit bins i just need to know what to change-----

i hope some one has done this.....maybe a better question is ::

is it WORTH doing......???

what else did i miss?

thanks
Mike

fiveoformula · Posted: Mon May 19, 2014 2:46 pm Post subject:

Whats the advantage of moving it?

MrMike98 · Member Joined: 18 May 2010 Posts: 231 Location: Bremerton

my understanding is that after awhile the plenum will get heat soaked and the mat will therefore be at a constantly higher temp. than actual air
so i heard some were some time about moving it-]
i believe on the OBD2 cars the mat is in the air inlet..

or maybe to much beer that day!!

anyway i am changing out my stock plenum for a ported one(to match rest of system)and i have the sensor in my face on the bench and it seemed like a good time to ask the question>
Mike

fiveoformula · Posted: Mon May 19, 2014 4:14 pm Post subject:

I would think that sensor would see a reading colder than usual all the time. and might have negative effects. May reduce fuel economy by running slightly richer, or it may do nothing. I have no idea, I probably would keep it in the same location until you know what it effects.

chevymad · Posted: Mon May 19, 2014 4:36 pm Post subject:

All depends on where it's tuned for. Your right in that actual air temp is probably closer in the intake tract. But if the chip was tuned for the temps it sees in the plenum then the tune will be off when you move it.

aaron_sK · Posted: Mon May 19, 2014 5:06 pm Post subject:

Cars with the MAT sensor in the aluminum plenum had closed sensors (solid brass, looks like a coolant sensor) whereas the cars with sensors in the airbox or throttle body had open sensors (plastic head, looks like a tiny MAF).

There is no doubt that having the sensor in the air intake is a better design, but as Brandon pointed out GM presumably designed the tune around the sensor.

Worth noting that the V6 cars of that same era had it in the air intake. No idea why GM stuck with that system on the TPI.

Bottom line: might be interesting if done alongside a full tune, but probably not worth it.

Alphius · Posted: Mon May 19, 2014 7:47 pm Post subject:

I had my IAT in the manifold on my HSR. Consistently saw temps about 10-15 higher than ambient. Like the others said, GM tuned for where the sensor is; I see no good reason to change its location.

Twilightoptics · Posted: Mon May 19, 2014 8:51 pm Post subject:

It does heat soak.

There are two styles of sensor:

Closed Element (Not as sensitive)

Open Element (More Sensative)

If you're replacing the plenum, move the sensor. All modern rigs I see now a days, diesel included, have it somewhere in the intake ducting.