Could somone please list all of the sensors on a MAF beta engine?

I'm pretty sure I'm familiar with everything, but I'd just like to make sure...

(I guess i could dig through hmaservice...)

 

MAF
Intake Air Temp
Crank Position Sensor
Cam Position Sensor
Oil Pressure
Engine Coolant (2)
Knock Sensor
Throttle Position Sensor
Idle Air Bypass (has a feedback, so it's sort of a sensor)

Thats off the top of my head. I'll post up more if I think of them.

 

There are two knock sensors aren't there? Block & body. Also the two O2 sensors wink

 

The body *knock* sensor is listed in hmaservice.com as an acceleration sensor.
There are also the oxygen sensors (not on the engine, but have a significant effect on the engine's operation).
The vehicle speed sensor is also not mounted on the engine but can affect the engine's performance if it's not working right....

I think that along with what Random posted is about it as far as sensors go.

 

Ok, so the current list is:

MAF
Intake Air Temp
Crank Position Sensor
Cam Position Sensor
Oil Pressure
Engine Coolant (2)
Knock Sensor
Acceleration/Body Knock Sensor
Throttle Position Sensor
Idle Air Bypass
Oxygen Sensors (There are 2 of them, right?)

One question... could someone explain the function of the idle air bypass?

 

Yeah, it's actually an inertia sensor of sorts, but it is part of the knock system. And the O2 sensors are as much a part of the engine as the MAF & IAT sensors are. They all directly affect the performance wink

Some of the non-related ones are things like the airbag sensors, ABS sensors(if you have ABS), stuff like the emergency brake switch, door and hatch switches and driver's seatbelt switch are hardly sensors, but they turn on lights so they are 'inputs' smile.gif

Ummm...give me a minute, I can probably think of more mundane little ones.

EDIT> The idle air bypass regulates the air to achieve a certain idle speed when the throttle plate is closed(i.e. you aren't pressing the accelerator). I believe that the ECU adjusts it based on the TPS and crank speed, but I don't thnk it usually provides feedback in the form of an electrical signal (which would make sense with Random's comment). It it my understanding that there are different types of bypass valve setups, but I think it is more of an analog feedback device--The ECU provides it a target, and it moves based on manifold vacuum, not on any 'sensor'. Sort of a self-sensing device. wink

 

The IAB provides feedback in the form of resistance. If you disconnect it, you should get a CEL.

It basically allows your car to idle with the throttle 100% closed. It also feeds the engine air when your foot is not on the gas, and you are decelrating. If you rev to 6000 RPM, then take your foot off the gas, the throttle slams shut, and the IAB stays shut...till the engine gets down to about 1300 RPM, then it opens to allow a *soft* fall to the 800 RPM idle. If it stayed 100% closed, your RPMS would actually drop below 800 before the IAB would open up to try to raise the idle. It would not be able to provide air to the engine fast enough, and the engine could die, or more likely, stumble down to about 500 RPM, then cycle up to about 1000 RPM, and then settle down to the *normal* 800 RPM idle.

The ECU can also *adjust* and *learn* how the IAB functions. Since I put out about .5psi of boost at idle, the ECU has learned to barely open the IAB to allow idle. For a N/A tibby, this small of an opening would not allow an 800 RPM idle.