Thread: wiring help

Hello all i am about to change the ecu to a nismotronic with map sensor can you tell me how to connect the aem 3 bar to the maf plug what is the color and the arangement, the iat sensor also the boost controller . and the high low boost switch what cables do i have to choose. if you have photos of your application that would be usefull the engine is sr20det red top rwd at a starlet kp60 thanks a lot for your help

You need to do your own research babe. There are a lot of info in this forum.

can u help me please?

MAP sensor official guide: http://www.nismotronic.com/Help/MAP_Installation.html
There are 3 wires coming from the stock harness to the MAF. They are:

- Ground
- Signal
- +12V

To install a MAP sensor, you want to reuse two of these wires. Ground & Signal. You CANNOT use the +12V, since a MAP sensor calls for +5V. Either wire a +5V feed from the NEMU breakout board, or splice your MAP 5V-in to the throttle position sensor harness, since that already has 5V.

I'm not gonna bother telling you colors that might/might not work. It's really simple to deduce though;
Probe the MAF plug, with no sensor attached.
-With the power OFF, find the wire that has ground continuity. That is your ground, mark it.
-With the power ON, find the wire that has constant +12V. That is your 12V feed. mark it.
-The last wire is your signal wire. Mark it.

The above mentioned method is the easiest, however, it might not be the best alternative. By running all 3 wires fresh to the breakout board, you eliminate issues that could arise from using an old wire harness. If you dont want to do this, go ahead and use the stock harness.

To install an IAT sensor is really the simplest of things. Here's the official how to install it: http://www.nismotronic.com/Help/IAT_Installation.html

Here is how I did it, since my ECU didn't have EGR.

You need a 4.7k resistor, and just follow this schematic.

If you are wondering what the resistor does, it shifts your usable sensor range from the unlinear orange line, to a more suitable blue one.

You can choose whatever ADC input you have free on your breakout board. 5V+ is also sourced here as seen from the above image.

If we move on to the Boost Solenoid, here's the official guide: http://www.nismotronic.com/Help/Boost_Solenoid_Installation.html

Really simple, two wire job. One goes to +12V, other one goes to ECU pin 102. I think you'll find the above mentioned links more than enough to complete your installation.

my advice, unless your taking the car to a tuner who knows how to use nismotronic and will take the time to get the tune right, do not use the maf wiring for the map sensor.. you can use the ADC "breakout box" to wire the maf up, that way if something happens you can easily go back to maf..

my car has map and iat sensors but i still run on my maf because i know how to tune it.. i can get my car to run on map but i cant get it dialed in perfectly so it has a few hiccups and drinks fuel like no ones business, i just use my map for boost control and datalogging

Not to knock down on you, but I think you are one of the few that has this problem. We don't want to deter anyone from running MAP. My car runs much better on MAP than MAF...

If your having to spoon feed someone information, speed density is probably not for them.

I'm sure the problem is with me not knowing how to tune speed density.. I can tune maf fine.

Converting to MAP was the best thing I ever did. Getting 36+ MPG on the highway. The setup guides Nismotronic offers are great. Also I suggest scaling your own IAT after it is installed by using an accurate thermometer and some hot and cold water. Start at cold or hot, and slowly mix your way to the other end, take voltage readings as you go.

you mean like this? http://www.sr20-forum.com/nismotronic/67330-prepping-map-conversion.html#post926062

theres a preset in nismotronic just for using the 4.7k resistor, several people have messaged me saying it worked perfectly for them an they did not have to adjust it. tho it never hurts to double check.


i want to clarify that speed density does have its advantages, and im not trying to tell people not to go for it, however if you are new to tuning it might not be the best place to start learning, however maybe thats not true since i started with maf and am having a hard time understanding speed density (basically just the iat conversion stuff so that it runs the same ALL the time) anyway, cheers to all an happy holidays.