Im in the middle of putting my crx back together and ran into a sensor which i dont know where it belongs or what it does. I believe it belongs somewhere inside the cabin and plugs into the body harness.

3 prong sensor which plug wires consist of 2 yellow/white with brown dash which is spliced together, green/white, and red/white

here are 2 pictures...help would be greatly appreciated



on the sticker it is labelled

SENSOR COMP, PA
079800-0821
PS 21 5 V
DENSO JAPAN

 

ive never seen one before but i'd be willing to bet that it might be the barometric pressure sensor that goes in your kick panel somewhere near the ecu i believe.

... After checking, it seems to me that it is indeed your atmospheric pressure sensor.

 

NICE!!! thanks for the info

now question is do i need it? if removed would anything happen.

Im in the middle of redoing my body harness and want to remove everything that isnt necessary anymore

 

im gonna go out on a limb and assume its probably quite necessary, since the maf is using it as a comparison to give more accurate readings. and if the maf is inaccurate thats gonna cause all sorts of unhappy issues. For all i know unplugging it might render the car undriveable or unstartable, but i really cant say for sure cause ive never unplugged one, or heard of somebody removing one.

 

thanks for all the great info

by anychance would you have a wiring diagram so i can rewire back into the harness. I dont want to hunt for a new harness and redo everything ive done...

all i know of right now is that the red/white goes to C09 on the ecu and the yellow goes to the 18 pin and the 6 pin...i just need to know where the green/white goes


Modified by ozrednsx at 11:54 PM 8/29/2008

 

hmm thats a good question. with the resource im using there does not appear to be any information pertaining to what each wire goes to. someone else will have to chime in on this one lol

 

alright...thanks for all the quick info

ill most likely dig into tomorrow and figure out where that last green wire goes.

 

I misplaced mine and lost a **** ton of gas millage

 

PA sensor wires:

red/white - sensor signal - goes to ECU pin C9

yellow/white - 5volt reference signal - connects with yellow/white from TPS sensor and goes to ECU pin C13

green/white - ground (all green/white at sensors are ground) - connects to green/white from ignition timing jumper, TPS, TW and IAT sensors and goes to ECU pin C12

sensor bolts onto passenger side just below/behind dash

 

How does it gauge pressure in the intake manifold if it's all the way down there?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by accordaffair &raquo;</TD></TR><TR><TD CLASS="quote">How does it gauge pressure in the intake manifold if it's all the way down there?</TD></TR></TABLE>the PA sensor measures the Barometric Absolute Pressure (BAP) which at any given altitude is the same everywhere, inside the car, under the hood or in the intake manifold (without the engine running) - as you go up in altitude, the BAP drops - at sea level it is about 29.92 in Hg (absolute atmospheric pressure of about 14.7psi)- here in Colorado where i am at about 6500ft altitude, it is about 23.55 in Hg (absolute atmospheric pressure of about 11.5psi) - as you can see, we have about 20% less air, so we require about 20% less fuel and the result is about 20% drop in horsepower for NA engines - the Manifold Absolute Pressure (MAP) is equal to the BAP before the engine is started - when you turn the key on, the ECU sets the MAP equal to the BAP and then adjusts air mass to fuel mass ratio from there based on engine speed, intake manifold vacuum and intake air temperature - once the engine is started, MAP = (BAP-vacuum) - the sensor is located inside the car to get a little more accurate reading as the BAP is also temperature dependent


Modified by jlicrx at 1:03 PM 8/30/2008