While I was at TechnoSquare this morning Tadashi showed me this slick little device... it's called a Techtom CMX-100 N2.

What's it do? It provides the following real time info as it's seen by our ECU. It also has a peak-hold feature so you can see the maximum value the ECU has seen.

Air Flow Meter Voltage (V)
Battery Voltage (V)
Ignition timing (degrees)
Intake temp (at the MAF sensor)
RPM (X10)
Speed (mph)
Water (Coolant) temp (F)

I learned a bunch about what's going on with my car in real time. I now know that my car's intake mods almost max out the MAF sensor's voltage.

How much? $195.00 plus tax.

Their phone number is 310.787.0847.


DaveO

2003 G35 AT Sedan / DP / Willow / Premium / Sport
350Z Air Duct, Eng Cvr & T-Stat / Stillen CAI / Crawford Plenum
GG 10-Wire Kit / TS ECM / E-Fans
Street Edge TC / B&M Cooler / Stillen Exhaust

 

What do you mean by max out the MAF's voltage?? Just because the air flows more, this uses more voltage?? Im very unclear, can you explain? Thanks!

 

I too need enlightening.

 

Here's a good explanation of the MAF and voltage from a thread we just had on maxima.org. We've had plenty of MAF failures so this is a frequent discussion.


The stock MAF is a thin, film-style MAF that incorporates a real thin piece of film, similar to photographic film. As wind enters the MAF assembly and flows into the film, the film's temperature drops. The ECU compensates for this drop by adding more voltage (in order to keep the film at a certain temperature). The ECU then measures this added voltage and uses it to determine the overall airflow.



Here's the thread it came from:

http://forums.maxima.org/showthread.php?t=316686

 

Dave,
Was the voltage maxed out during a dyno or during some heavy throttle driving?
Maybe you need to wrap some fabulous duct tape around the Pop charger filter to choke it off a little bit!

 

In a hundred words or less?

The mass air flow (MAF) sensor measures a portion of the intake air flow. Nissan's MAF sensor is the hot film type. The ECM (ECU) provides power to the hot film. The temperature of the hot film is controlled by the ECM to predetermined values over an established operating range (Approx. 1V to 5V on the 2003 cars). The heat generated by the hot film changes as the volume of air flow changes. The more air flow, the more heat loss. The more heat loss, the more power the ECM must supply to maintain the hot film at temperature. Less air flow, less heat loss, less ECM power required.


DaveO

2003 G35 AT Sedan / DP / Willow / Premium / Sport
350Z Air Duct, Eng Cvr & T-Stat / Stillen CAI
Crawford Plenum / GG 10-Wire Kit / TS ECM / E-Fans
Street Edge TC / B&M Cooler / Stillen Exhaust

 

I was wondering a few things...
Does it need to be wired in or does it plug in directly??? if it plugs in,where???
Can it be ordered online or will I need to call???

Seems like it provides alot of helpful info...can it be permanently mounted in the car or is it for dyno runs only???

Any other info you can provide will be appreciated..
Thanks
Russ
on1whl@hotmail.com

 

Russ,

The unit plugs into your OBDII diagnostic port.

You can permanently mount it or use occasionally for dyno runs or whatever. It comes with double sided tape and a couple of wire ties.

Here's TechnoSquare's website ---http://www.technosquareinc.com/index.html

Their phone number's included in my lead post.


DaveO

 

Is this item capable of logging values? If so, any idea how many samples per second it takes? The only reason I ask is because I have the pocketlogger www.pocketlogger.com Basically the same thing, plugs into the diagnostic port as well, but used in conjuction with a PDA it can log values as well as chart them.

 

did you take readings of the MAF voltage before your intake mods?

 

cyberz350,

Is this item capable of logging values? - No.

It does have a have a "peak holding" ability.

The pocketlogger is much more powerful, but I don't have a PDA. This little stand alone unit works pretty well for me.


apex locator,

No, I didn't measure the MAF sensor voltage when my intake system was stock. I had no way to do so at that time.

FYI. Tadashi was the one who noticed the high MAF sensor reading when we were "test" driving my car.


DaveO

 

Easy Installation ??

 

thats dope i will get 1 for sure

 

So is pocketlogger beter than the techno squar unit?

 

the CMX-100 is simply plug into OBD2 port and thats it.. you can cycle through the different modes with a press of a button-

same item used to tune my Z during prototyping- good stuff..

 

if you have a PC in your car, or a laptop, talk to chazz; he has the same thing, but it does log, and offers more items to check as well. its good stuff. but does require a PC with a serial port to run it.

 

Need favors from those folks who have the Techtom CMX-100 N2, pocketlogger, etc.

Please provide your intake air temperatures at idle, low speeds and approx. how long it takes to cool down after you get to highway speeds.

If possible I'd also like the same information from the stock 350Z and G35 air intake systems, as well as the JWT Popcharger w/heat shield, Injen, AEM, Nismo and K&N systems.

Why? Even though my G35's Stillen CAI filter enclosure (heat shield) and Z-tube are insulated, I was very surprised at the level of heated air my MAF sensor sees at idle and low speed running. I was also very surprised at how long it took for the temperature to come down at 65 - 80mph.

This information should benefit our collective knowledge.


DaveO

 

This might help in the design of my new Ice Cube Intake system. Well, maybe not, but anything that can lead to less hot air or less heat soak will lead to more effective power.

 

your question depends heavily on the temperature outside.

at 84degrees, my idle intake temp peaked 140degrees at one point. during 35mph and up itd go down within seconds to about 95.

that is all stock.

 

You're absolutely correct. We probably need a list of parameters.

Heres an example for consideration.

Car: 03 G35 Sedan
Air Intake System: Stillen CAI w/Popcharger air filter & Z-tube - System, including MAS Air Flow sensor, is fully insulated.
Ambient Temp (dash readout): 75F
A/C System: Off
Radiator Fans: Off
Water (Coolant) Temp: 190F - 200F
Intake Air Temp @ Idle for 3 minutes: 128F
Intake Air Temp @ 70mph: 84F
Approximate Cool Down Time: 3+ Minutes


DaveO