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View Full Version : maf hz stuck?


Cloud
07-11-2004, 03:35 PM
I have the older version of the maft and ever since I installed it I have noticed something strange. My maf hz never go above 1603.9hz. It reaches this quite early on, sometimes around 3500rpms and all the way to redline it just stays there and doesnt go over it. I find it a little hard to believe that the maf hz will be the same at 6000rpm wot and 3500rpm. is there a known problem with this in the older versions or should I be looking at the maf to see if it is bad? the maf seems to work fine in all situations prior to that and it still runs 'ok' even then although I have had to richen up wot significantly to avoid knock. is this normal for the maft? It doesnt seem right to me.

admin
07-11-2004, 04:07 PM
If you are using a pocket logger or other device that is as high as it will read. the computer will see a higher number
Mike

Cloud
07-12-2004, 10:22 PM
are you positive of this? I am pretty sure I saw greater hz values when I put the stock injectors back in and got fuel cut. how does everyone else log their hz values past this point then?

btrux06
07-13-2004, 03:37 AM
that is 100 percent true, the logger will only show up to 1600 hertz, u have to monitor the hertz on your afc , u do have one id imagine. the afc will show how much the ecus is actually seeing, which has ranged up to 2800 for some people

kpt4321
07-13-2004, 10:41 PM
are you positive of this? I am pretty sure I saw greater hz values when I put the stock injectors back in and got fuel cut. how does everyone else log their hz values past this point then?

The ECU's output to the logger will never show more than 1606, unless you have modified the ECU's code.

I have come up with a way to modify the code so that it doubles the range of the value going to the logger; for my car, I just multiply what I see on the logger by 2, and that's my airflow. I have seen up to about 2400 Hz on the 14b on pump gas.

kpt4321
07-13-2004, 10:42 PM
the afc will show how much the ecus is actually seeing, which has ranged up to 2800 for some people

More, really.

My car pulls 2400 at ~19 psi on the 14b!

My friend's car pulled a little bit over 3000 this weekend with the EvoIII16g at ~26 psi, on the dyno and on the drag strip. I think it was like 3006, or 30022, or something like that.