can someone please explain to me what an ECU is and what it does and same thing with the o2 sensor what do they do.......(Yes Im Dumb and Yes Im trying to learn so please help me : ) )

 

ECU-automotive computer
02 sensor-device that measures oxygen content in exhaust to correct air-fuel ratio

sorry, thats all im good for right now

 

ok so why would you want to correct the air/fuel mixture can you give me a example cause im trying to comprehend all this stuff : )

 

Maximum power is produced at the correct (stoichometric) ratio of fuel to air. (approx 13 parts air to 1 part fuel, by weight)
Varying the fuel ratio up or down lowers power.
Also a higher fuel ratio wastes gas (poor miles per gallon)
and a lower ratio raises combustion chamber temperatures, risking engine damage.
As you are driving along the 02 sensor detects a improper fuel/air ratio and sends a signal to the ECU. The ECU then sends a signal to the fuel injection to adjust itself.

 

The ECU for Mazda actually stands for Emissions Control Unit. It is the source of many headaches and its main reason for existance is to monitor and control various functions around the engine. Mainly its there to reduce the pollutants that your car emits (a problem that I am having at present...). Hence the O2 sensor. This senses the amount of Oxygen in your exhaust. Its there to see if your emissions controls are working and to send a signal to the ECU to adjust certain things to actually INCREASE the amount of oxygen in the exhaust. More Oxygen=less pollutants. Can someone correct me if I am wrong?

Rat

 

thanks man that pretty much clears up my question i have one more for ya could i just take out the stock intake box and just put a cone intake right there on it?? theres a little hose that runs right into my stock intake box and i dont' know what it is for and i want to know if i can just leave it sitting there or if it needs to stay in the intake box cause i dont' want to screw anything up do you have any clue what i mean??

 

The big hose coming from your intake that doesnt go to the throttle body is clean air for the Air Pump. And if you remove your intake for a cold air system, you still have the AFM to deal with as far as I know. What I know for sure is that 7s wont run without that sensor. I learned that the hard way.

 

damn heh i guess im just going to have to pay someone to put that on cause i don't know enough as it is and i don't want to **** anything up i wounder what if ICEMAN or AEM i wounder if they make a cold air sys for my car i know HKS does but im not down with the hole sponge thing just cause it tends to harden and then flake off!or thats what i heard

 

oh another thing what is my AFM??

 

Alot of the guys here dont even run air pumps, and I bet that most of them also run cold air systems. They arent that hard to install... I am just giving you some info from my experiences so far. There is a sensor, in the metal box below the air filter assembly. In stock form, your car wont run without it. The air pump is emissions only, so if you are ever so lucky as to not have to recertify every year like I do, look up some of the threads on airpump removal. Its a little more complicated...

Rat

 

I may be messing this up, but the AFM is the Air Flow Meter. It is basically a flap valve below the air filter in a silver metal box that gives the ECU an idea of the amount of air being pulled into the intake tract. The voltages it sends differ depending on throttle position.

 

ok thanks man for the info

 

In the future the forum has a search function, all of your basic questions have been answered a million times before so a quick check of the forum should produce great results.

Oh and have fun with the 7

 

i did a search for it and nothing came up

 

You might want to download the factory service manual at http://www.iluvmyrx7.com/Technical_I...ice_manual.htm to disc or print. Its very free. You can download a section at a time or the whole thing.