MazdaManiac

iTrader: (3)

The control signal for the MAF is 5v.
If you are seeing 12v ANYWHERE on the MAF harness, you have something seriously screwed up in the wiring.

Brettus

iTrader: (2)

/\ should see 12v on the Black/blue wire ,
0.6v on the yellow wire (only when connected to maf)
5v on the Red wire when not connected and 2.2 v when connected
Black white is commmon return to PCM (I think)
Black/Green is sensor earth

Derex'8

iTrader: (4)

Yeah will run a check again. Just for clarification, when testing w/multimeter on what setting should I put the selector on?

The wiring leading up to the maf checks clean...

Have 2 more things I'm going to try, check some more wiring, and replace maf which is on the way.

The Maf is powered from the Main realy right?

The main realy is powered from the ignition circuit?

And lastly what are the power sources for the 2 wires to the cigarette lighter?
The yellow wire and the Red/black wire?

I have reason to believe, from research, that a short in my boost gauge wiring may be the culprit.



And Jeff your current avatar tops all so far...

Brettus

iTrader: (2)

12 volts or more

Derex'8

iTrader: (4)

I have a digital multiple range multimeter and do I put the selector on DCV? when testing maf

How about the test leads, I do use both right?

Brettus

iTrader: (2)

yes DCV - 12 or more

connect your black earth lead to the battery negative terminal and then use your red to test the pins on the plug . If you grind the end of your probe to a sharp point you can test the wire with it plugged into the maf by piercing the plastic around the wire .

PS - don't push the probe through your finger

Derex'8

iTrader: (4)

Cool thanks for clearing that up for me.

I was wondering so how is the ecu getting load now?

I'm getting correct maf g/s readings but as stated voltage is pegged

I just couldn't resist tonight and said F%^k it. I hit 6.5 psi. Car stumbled a bit @ around 4 k rpm,(from to much fuel), but pulled through and hit hard(and I mean w/neck snapping a vengeance) boost and gear transition was as smooth as butter. Then stumbled and bogged down again from overly rich conditions.

MazdaManiac

iTrader: (3)

Ahh, right. Forgot about the source for the IAT sensor.

THIS IS NOT POSSIBLE.

If you are asking how to use a multimeter, how do you know the MAF is pegged? Where are you getting this information from?

Derex'8

iTrader: (4)

From the AP itself, will post datalogs up tomorrow so you can see and just thought I ask to make sure I was using the multimeter right and I was...

MazdaManiac

iTrader: (3)

So, the AP is reporting a MAF voltage of 5v all the time, but the actual g/sec of the MAF is following the engine load?

Yes - log please.

Derex'8

iTrader: (4)

Here is how my MAF harness side checked out

11.54v Black/Blue
.03v Black/White
.03v Yellow/red
5.02v Black/Red
.03v Green/Black


Don't know how to post the actual screenshot from excel but here goes; First one is on freeway and the second is WOT

Okay edit just made them into zip files and attached

dannobre

iTrader: (3)

Must be an AP issue...the A/F is changing...and the airflow reported changes as well..even with the MAF pegged at 4.99 volts all the time

Derex'8

iTrader: (4)

But I'm also getting a P0103 CEL

Brettus

iTrader: (2)

Your wire voltages look fine although i don't see how you get any voltage from an earth wire unless it is meter error

Perhaps the 4.99 reading from AP is the temp sensor voltage

MazdaManiac

iTrader: (3)

You are on an old firmware, aren't you?

dannobre

iTrader: (3)

103 is MAF voltage too high...not surprised

Derex'8

iTrader: (4)

Well I've narrowed it down to either a malfunctioing MAF sensor or corrupted ECU.

I've done pretty damn near everything

Thought it may have been the ap so uninstalled and removed all software and maps from computer, car, and the AP itself. Reinstalled & updated everything, went to start car and still through the damn cel and Maf pegged.

Will find out the verdict thursday when new Maf arrives

Derex'8

iTrader: (4)

Nope and running your new version map

MazdaManiac

iTrader: (3)

I just don't see how it is physically possible for the MAF output to stay at one voltage while showing a change in airflow.
They are completely dependent on each other.
5v at the MAF is about 370 g/sec or so. It should just stay pegged there.

dannobre

iTrader: (3)

How about the AP seeing the same voltages........ie reporting wrong values

Do you have another datalogger you can try??

Brettus

iTrader: (2)

/\ if he used his multimeter to check changes in voltage on the maf wires while in operation (at idle with someone reving the motor), that could rule out the AP as the problem ..... perhaps

MazdaManiac

iTrader: (3)

Yes - if the MAF voltages are equal to what the AP is showing, then that is what they are.
I just can't figure out how it is possible for the MAF to produce varying flow values if it only sees one, fixed voltage.
There is something fishy going on here.

dannobre

iTrader: (3)

The really strange part is the values don't look really strange given the other values??

Something is really confused

Derex'8

iTrader: (4)

I dunno it's beyond me I haven't tried the multimeter reading while car was idling to confirm the AP readings but will give that a try tomorrow.

But I don't think it's the AP showin showing bad readings because my car still throws a CEL as well as my Traction control light

BTW why is my traction control light on as well?

MazdaManiac

iTrader: (3)

Ahh, the plot thickens.
The TC light goes on when the MAF fails completely or if the TB or MAF are unplugged.

I just went outside, took an alligator clip and shorted across my MAF to simulate what you are getting.
The car wouldn't start cold.
So, I undid that, started it, got it warm and then tried it again.
It was very, very stubborn, but it started eventually.
It is completely undrivable. It won't accelerate at all and the MAF reads 370 g/sec fixed.

So, you have something else going on there.