AE86 MAP sensor values

totta crolla
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AE86 MAP sensor values

Postby totta crolla » Wed Mar 27, 2024 8:44 am

These are U.K AE86 MAP sensor values (unless anyone knows any different :?: )
Min volts 0.87
Min kpa 21

Max volts 3.80
Max kpa 114

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jondee86
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Re: AE86 MAP sensor values

Postby jondee86 » Fri Mar 29, 2024 2:33 am

I don't remember ever seeing any specific values for the AE86 MAP sensor.
When I used the factory sensor on an aftermarket ECU the calibration was
basically connect the sensor to the ECU and power it up. Learn the sensor
value at 100kPa(abs) and then pull a vacuum on the sensor to say 25kPa(abs)
and learn that. The sensor curve will be a straight line between those two
points so the ECU just interpolates the values at any pressure in between.

What kind of MAP signal information can you read from your ECU if you hook
your laptop up ? Can you see what value it is reading at atmospheric and
when you pull a vacuum on the sensor ?

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

totta crolla
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Re: AE86 MAP sensor values

Postby totta crolla » Fri Mar 29, 2024 4:03 am

The AEM ecu requires max and min voltages plus max and min pressures, it does not have a learning facility.
I used a MAP enabled AE86 specific Freedom ecu to read the pressures and the AEM to show the voltages, the voltages are not affected by calibration changes.
A Mityvac was used to obtain the vacuum.
There is no viewable graph in the AEM but l guess it can be assumed the MAP sensor is linear.
Atmospheric pressure is available on both ecu's

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jondee86
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Re: AE86 MAP sensor values

Postby jondee86 » Fri Mar 29, 2024 3:08 pm

Looks like you got good values. By way of comparison here is a generic old school
Toyota MAP sensor graph that I pulled from Toyota Autoshop. I've added the kPa values
to make life easier :D

Image

I don't think you are going to see 114 kPa on a N.A. engine so I would be inclined to
set the max value at 100 kPa. That will match your fuel map and make sure that you
get to the top row of cells at WOT.

Cheers... jondee86
The reasonable man adapts himself to the world; the unreasonable one
persists in trying to adapt the world to himself. Therefore, all progress
depends on the unreasonable man.

totta crolla
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Posts: 654
Joined: Tue Mar 26, 2013 5:21 am
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Re: AE86 MAP sensor values

Postby totta crolla » Sat Mar 30, 2024 10:50 am

Brilliant!
Thanks for this and l'm happy the values l'm using are close to ideal.
I will use 3.64v - 100 kpa as shown.