Okay I have thrown for the 3rd F&*king time the P0103 code. It's time to get to the bottom of this, I've had enough.

This problem first started way back last year, I ended up replacing the entire maf sensor itself as the wiring checked out fine.

Everything was ok up until exactly a yr later...which was approximately 3 weeks ago I threw the same damn code, I again proceed to check the wiring see a small knick on one of the maf wire (The black/white one) I fix it and solder it back. I also notice that on that same wire the connection looks a lil sketchy at were it meets with the maf clip.... nothing big though just another small knick. I fix those & replace the maf once again. (After i fixed the wires I checked the voltage via the AP and it was still pegged @ 5v, so I was thinking that the maf sensor must be busted from the faulty wire)

Problem resolved or so I think 3 weeks later here I am again. This time though my + terminal on my battery came loose, I popped the hood notice it, retighten it back and when I go to start the car VOILA!!!! The God forsaken P0103....My maf voltage input is pegged @ 5v..... Seriously I need some help here.....Put me in the right direction....Is there a fuse for the maf sensor?......

 

have you tried fairy dust? im just saying!

Perhaps grounds? or get the alternator checked

 

But no seriously....is there a fuse built within the MAF sensor itself? I'm thinking along the lines that I have some faulty wiring to the maf or something that is sending a high current of voltage to the maf sensor, and I've yet to address it, hence why I keep busting the maf. If this is true, then why, when I replace the maf it doesn't blow right away and the voltage readings to the maf read perfectly fine?......

 

Nothing that I see on the electrical schematic.
Unless I'm wrong, the MAF seems to run right to the PCM. I doubt it's fused inside the the MAF housing.
I'll have to think about this some more, but thinking that a bad ground might do this.


So.............how did these wires ever get knicked in the first place?

 

I'm thinking from my first go naround when I wanted extend the wiring w/out cutting it. I had to cut and strip some of the black wrapping around the wires so I could get a extra inch or two of length.

 

Better look all that wiring over really, really good and make sure you have all the nicks covered up real good. I'm wondering if you aren't getting a short somewhere from time to time.
I'm also assuming your soldering skills are okay?
I went over the P0103 diagnostic and repair procedure and I don't see much that would help you. Worst case scenario is PCM is bad, but I don't see that being a real possibility right now.

What kind of intake do you have? I've read some posts where AEM have caused issues with wetness.
I assume you have cleaned this MAF very carefully and also inspected for other potential vacuum leaks?

 

well G3tr3ddy2gr3ddy is supposed to be sending me the maf clip/connector & wiring, just awaiting that. If it is the wiring then will I still need to replace the maf senor itself?

 

Only if it was something that simple...There is definately no vac leaks whatsoever and I actually have a whole new intake setup now. I'm using a foot long 3.5" OD Maf housing for my pull through setup.

 

Sounds like a bad ground to me.

 

A couple of questions......

Which of the wires is ground for the maf?

Will I still need to replace the maf sensor itself if it's indeed just a faulty wire?

When I first ran into this problem someone had suggested I run a check with a multimeter and had listed the voltage I should be seeing for each wire. I need to find this info & run a check

 

if youre MAF is always seeing 5v, check for a short to B+.

And there is no fuse inside a MAF housing.

MAF should be a 3 wire sensor if I remember correctly.
Should have power, ground, and and signal wire.

Power should have B+, signal wire will have the 0-5 volts reference signal (in reality, if you have 0 or 5 V you have a problem. Ground shouldnt be dropping and V.

Do you have 5v with KOEO (key on engine off) or with KOER (key on engine running), or both?

If you have 5v KOEO you definetly have a short to B+ or a PCM issue. Even with KOER and 5v I would guess a short to B+

 

5v with KOER could be an internal short in the MAF between the power/signal wire, but I'd doubt it.
If anything, swap with a known good MAF.

 

I'm seeing 5v via the ap with KOER & KOEO. I'v done better than that and have replaced the maf sensor 3 times w/brand new units, & each time the problem would be resolved for a certain amount of time & rear it's ugly head again.

Our maf has 5 wires

green/black
white/black
blue/black
red/black
yellow/black

I found that thread I was referring to here

I'll run a multimeter across the maf harness side and check the voltages

 

Okay the problem is back again fellas!!!!!I have officially had it, I'm taking it in to the Mazda dealership, tomorrow... I think the Maf drive to the ECU is shorted...What do you guys think?

 

Derex, Pm'd

 

Still no responses anyway I did some research and found that the terminal A on the maf runs to terminal C on the main relay (EGI) I'm going to pull it & check for continuity

 

Can anyone tell me exactly where the maf Grounds to on the chassis?

 

Okay could someone answer me this please. Let's say it is a faulty ground somewhere. Could I possibly splice into the grnd wire for the maf and ground it directly to the chassis?

 

^ umm you should be able too unless im overlooking sth that shouldnt be a problem

 

almost the same issue going on with mine... drive's like crap if it even run's with the maf plugged.. run's like a champ with the sensor unplugged , but the battery die's within a day

 

Derex.... you had a loose battery connection then you got the Cel.

Did you clear and move on......?

P0103 could have been caused by the bad battery connection.

Clear it an move on.....

Then if it comes back...?

 

MAF most likely grounds through the PCM.

If youve gone through that many MAFs its either a wiring issue or a PCM issue.