Log RPM not equal to actual RPM - Solved

[yeastieBoB]

I went for a drive to take some logs for dialing in FN035. The RPM (NE) in the log appears to be lower than actual RPM. I let off ~6500 and the highest WOT RPM my log shows is ~4900. My shift light did come on and it's probably set around 6500. The highest RPM in the log is 5100.

I took two logs and the RPM in both seems off.

What could cause the RPM to be understated and what impact would that have on the engine?

[yeastieBoB]

Anyone have any ideas?

I think the OEM tach gets its signal from the coil, but not sure. I know my aftermarket tach does.

No clue where the EEC gets its signal.

I'm at a loss to why the log wouldn't match the tachs.

[SlowBox]

I've noticed the same thing and it's never been resolved fwiw. Tried grounding the distributor, adding grounds at the eec, and still showing 5400 when it tags the 6k limiter.

[yeastieBoB]

How did you handle adjusting FN035?

[decipha]

i have a histogram setup for fn035, if you click the history table button two buttons to the right of the show dashboard button it will pop up with the histogram tables

click on his_perload_err table from the drop down, then select running average from the next drop down under view, do a wot pull and the perload error will be saved in the far right column (730+ tprel)

as for the rpm not logging correctly, i changed the rpm payload from the filtered value to the raw input calculated value, if you download the latest gufx adx on the homepage and re-apply the universal adx patch code to your tune it will log the faster rpm value

https://www.efidynotuning.com/downloads.htm

[yeastieBoB]

i have a histogram setup for fn035, if you click the history table button two buttons to the right of the show dashboard button it will pop up with the histogram tables

click on his_perload_err table from the drop down, then select running average from the next drop down under view, do a wot pull and the perload error will be saved in the far right column (730+ tprel)

as for the rpm not logging correctly, i changed the rpm payload from the filtered value to the raw input calculated value, if you download the latest gufx adx on the homepage and re-apply the universal adx patch code to your tune it will log the faster rpm value

https://www.efidynotuning.com/downloads.htm

Thanks, I'll try that with the history table.

I do have the latest adx, but I'm not sure if I reapplied the patch code to my tune. How do I do that?

Also, is NE RPM the correct value to look at?

[decipha]

I do have the latest adx, but I'm not sure if I reapplied the patch code to my tune. How do I do that?

Also, is NE RPM the correct value to look at?

I haven't made any changes to the adx logging file since last year. You dont have to change the adx file.

you have to get the latest GUFX XDF file from the homepage.

delete your old xdf file and load the new one in tunerpro. Load in your current tune file .bin

click on the universal adx logging patch and it will show that your tune is not patched. Apply the patch.

then log and youll see its faster now

[yeastieBoB]

I do have the latest adx, but I'm not sure if I reapplied the patch code to my tune. How do I do that?

Also, is NE RPM the correct value to look at?

I haven't made any changes to the adx logging file since last year. You dont have to change the adx file.

you have to get the latest GUFX XDF file from the homepage.

delete your old xdf file and load the new one in tunerpro. Load in your current tune file .bin

click on the universal adx logging patch and it will show that your tune is not patched. Apply the patch.

then log and youll see its faster now

Ah, I see what you mean. I've done that with other XDF files, but didn't remember. Thanks for the help!

[yeastieBoB]

I finally got out to try again, and it looks like the latest GUFX is logging RPM correctly now. Thanks again Decipha.

[decipha]

no doubt