11 replies to this topic

[Arkymiata]

I'm in the process of setting up a AIM MXS system in my 99 build. I believe that I have all the sensors figured out except how to capture data from the throttle position sensor.  What is normally done. Do you tap into the existing TPS on the car or add a AIM sensor like a string pot or Potentiometer? Any help would be great

[ChrisA]

Tap into the TPS lines. Becareful when referring to the FSM on determining the wire colors and/or Pin order. I noted dissimilar orders indicated in a couple places in the manual when I was verifying & testing prior to my install last winter.

[Arkymiata]

I think I figured out the TPS wires. What about water temp do you tap into the ECU water temp sensor or add a independant water temp sensor at the back of the head?

[Jim Drago]

add a sensor

[38bfast]

add a sensor

why?

[Marc Cefalo]

why?

jim means add a sensor for water temp....i think..... as the NA and NB obdII info refresh rate is so slow, it would never work for datalogging.  tps reading on 1.8's at the sensor or wire at eco is a breeze 

[Jim Drago]

jim means add a sensor for water temp....i think..... as the NA and NB obdII info refresh rate is so slow, it would never work for datalogging.  tps reading on 1.8's at the sensor or wire at eco is a breeze 

correct

[Foleyracing3]

I would recommend keeping the aim independent from the ECU. Aim sensors are much more accurate and faster than the stock ecus.

[manthony121]

I am also looking at installing a complete data collection system in my NA Miata.  My plan is for a MXP dash logger, Smarty Cam, and independent sensors for brake pressure, throttle position, steering wheel angle, oil pressure, oil temp, and water temp.  I think the whole setup will be worth more than the car itself!

[JJ Servis]

I am also looking at installing a complete data collection system in my NA Miata.  My plan is for a MXP dash logger, Smarty Cam, and independent sensors for brake pressure, throttle position, steering wheel angle, oil pressure, oil temp, and water temp.  I think the whole setup will be worth more than the car itself!

 

I have this setup...  its niiiicee

[RWP80000]

I would recommend keeping the aim independent from the ECU. Aim sensors are much more accurate and faster than the stock ecus.

 

I think the above is a very good and appropriate recommendation.  For those running data acquisition systems, it may be time to take a close look at the language under the GCR SM class rules, "9.1.7.C.1.o Electrical Equipment",  specifically paragraphs 5. thru 7.

 

Under paragraph 5. the second and third sentence unambiguously state "No circuit modifications are permitted. The ECU maps and inputs (my underline for emphasis) must not be modified." 

( Can anyone guarantee that tapping into the engine harness wiring to feed a data acquisition system with a voltage signal is not potentially "modifying" the signal that is seen by the ECU? 

 

That is the reason for the language in the next paragraph 6. which says in the third and fourth sentences;

 

" Any sensors required for analog type gauges must be in addition to the Mazda sensors.  Data acquisition sensors may be added."

 

I know it is possible to successfully tap into the engine harness and obtain a signal for your data acquisition needs, but due to the inability to know the actual affect of doing so on the signals to the ECU, it is not authorized by the rules. It also keeps the stock Engine/ECU wiring harnesses from being unnecessarily compromised and complicating technical inspections.

 

Rich Powers

[Tom Hampton]

( Can anyone guarantee that tapping into the engine harness wiring to feed a data acquisition system with a voltage signal is not potentially "modifying" the signal that is seen by the ECU?  

Nope.  It abolutely DOES alter the signal.  Maybe not by much, maybe not enough to matter...but, one would need to know a lot more about the ECU internals to answer THAT.