TMO Question

[anoldsman]

I am logging with the TMO data logger and I have a question. Is the injector pulse width the actual pulse width or just a baseline? In other words, does the computer use the Low/Mid/High/O2 trims to add or subtract from the injector pulse width? Also, as anyone ever flow tested the factory MAF to correlate between the Hz and air volume?

Thanks,
Chris

 

[Blk_99gst]

Also, as anyone ever flow tested the factory MAF to correlate between the Hz and air volume?

Are you talking about karmen hz you would see from a safc, versus the lbs/min airfow you would see on a logger? You can't really corrilate between the two. The safc see just karmen hz, the frequency that the maf is reading air passing through it. The ecu then uses this karmen hz number, along with air pressure, temperature, to get the lbs/min number. So you really don't have enough information to calculate between the two.

 

[kpt4321]

The IPW is the length that the ECU is holding the injector open.

Like Blk_99gst said, you can't convert from MAF Hz to air volume without additional information.

 

[anoldsman]

Are you talking about karmen hz you would see from a safc, versus the lbs/min airfow you would see on a logger? You can't really corrilate between the two. The safc see just karmen hz, the frequency that the maf is reading air passing through it. The ecu then uses this karmen hz number, along with air pressure, temperature, to get the lbs/min number. So you really don't have enough information to calculate between the two.

I understand. I was just curious if anyone had tested the MAF on a bench to see what Hz is equivalent to what air volume. Then the baro pressure and the intake air temp could be used to convert to air mass. Again, No problem I was just curious.

Chris

 

[anoldsman]

The IPW is the length that the ECU is holding the injector open.QUOTE]

So the IPW is the actual pulse width after all trims are compensated for?

Chris

 

[kpt4321]

Yes, it is.

Keep in mind that Hz corelates to air speed, and then you need to d another conversion to figure out the volume.

Sometime in the future, probably the near future, I plan on doing some testing to find out aproximately what the conversion rate is. Right now though, no dice.

 

[anoldsman]

Thanks for the info.

Chris