mass air flow sensor

[smartHHO]

Does the car have it?

I am using Pro Scan OBD II software, and it works except fuel economy. They say you need a MAF sensor installed which some new cars don't have. So, did they not put one in the smart?

Thanks in advance.

Eric.

[jetfuel]

...HHO...good one....from the tech manual out of the members page I looked at the fuel delivery system and saw nothing in it that was refered to as "MAF" sensor...

jetfuel

[smartHHO]

Originally Posted by jetfuel

...HHO...good one....from the tech manual out of the members page I looked at the fuel delivery system and saw nothing in it that was refered to as "MAF" sensor...

jetfuel

Figures.

well, at least I can read the speed, rpm, codes, Oxy sensors, temps, 1/4 mile times, torque vs rpm.

Not a bad program and my OBD cost me 30 bucks off ebay.

[SmartDigger]

That is good...they are real easy to flat line.

[VinceLA]

It uses a MAP sensor.

[LittoDeviL]

ECU's in vehicles use either a MAP (Manifold Absolute Pressure) sensor or a MAF (Mass Air Flow) sensor. Both have their pro and con but in the case of the bosch ECU in the smart car, they don't have a MAF sensor just a MAP.

MAF is more accurate but it also more restrictive then using a MAP sensor as the MAF has basically the sensor inside the intake tube and in a high performance setup this can restrict over all air intake velocity.

I can go more indepth but yea..

I just use my scangauge and watch the MPG change up and down

Larry

[jetfuel]

...thanks Larry....intake manifold pressure sensor..B28......duh...just needed to open my eyes...

jetfuel

[jwight]

MAF has basically the sensor inside the intake tube and in a high performance setup this can restrict over all air intake velocity.

I'm sure the "high performance" of the 70 hp engine is what precluded use of a MAF in the smart, although it doesn't seem to affect the 430 hp LS3 Vette engines much.

[LittoDeviL]

Originally Posted by jwight

I'm sure the "high performance" of the 70 hp engine is what precluded use of a MAF in the smart, although it doesn't seem to affect the 430 hp LS3 Vette engines much.

No I agree that it doesn't affect the vette engine much but it does affect it to some degree as the MAF has an actual air sampling sensor inside the intake tube. The benefit is that you have something a lot more accurate compared to "guessing" but the con of that is the sensor itself does take up space inside the intake tube. On the flip side, as technology gets better and with enough info, "guessing" the amount of air going into the engine gives the same result as an ECU that has the MAF sensor but without anything disturbing the air flow.

Some MAF sensor are pretty restrictive and some are not. Just like regular factory CAT and aftermarket high flow catalyst converters. They all have their pro and con's..... as you point out.. to various degrees ;)

Personally I would choose to have a MAF =P... from what I recall it's just a wire or two that senses how much air is flowing pass it by how much the wire is being cooled down.

Cheers!
Larry