Hi everyone,

I am running a pnp speeduino which when it works as it should is really nice, but I am having this issue where sometimes my engine will run really rich for (as far as I know) no reason on the same tune it would normally run absolutely fine on in every condition.
I would start my car up and it would seem as if I just increased my whole VE table by a whole bunch, I mean the car will never go above 13:1 AFR no matter where I am on the table. Then when I shut it off and start it again it would be back to normal or do it a few more times if I'm unlucky. I checked for all the obvious stuff like WUE, ASE and IAT density to see if I somehow messed that up but no. I checked some logs and it seems like it would, for no reason, just add a whole bunch of duty cycle to the injectors (idle is normally around 1.5ms and when the issue is occuring around 1.9; while coolant temp is the same), which would suggest that my issue lies within the tune or ecu and it is not mechanical.

Now I am for sure no tuning pro so I could be missing something or there's something wrong with my ecu. I hope someone can help me with my problem, it would be much appreciated.

Thanks!

Mats

 

I suggest posting your tune as well.

 

oh **** of course, me dumb.

 

I don't know much about the concept of including Barometric Pressure in you fueling equation directly, but I would not do it.

Your issue is that, because the above, During "No Issue" your Baro was read as 99 kPa. During Issue, your Baro was read as 84 kPa. You should probably find out why the occurred, but I would change the Fueling table from Baro to Incorporate and re-tune. Not being familiar with your controller, I would hypothesize that my preferred settings would change from the 1st pic to the 2nd pic:



What you have, which seems to have the Baro directly in the fueling equation.



I'm not sure about this, as the instructions do not mention the "Fixed" setting.

 

Wow I didn't notice the change in baro, but I also didn't consider that that was a possibility as I live in the Netherlands which is flat as ****. Hmmm, anyone have an idea what could cause the sudden difference? I'm gonna switch the map ratio to fixed and check if it still does it. Thanks for the help

 

Does your ECU have the dual MAP sensors? The newer board revisions have a separate sensor for baro pressure.

Check which sensor the ECU is using to get baro pressure in the settings.

If it's the same sensor as the MAP sensor, you need to wait a few seconds after key-on before cranking to allow a true baro reading to be taken.
Otherwise the engine will pull some vacuum when cranking and your baro reading will be incorrect.