I am tuning my single turbo 2v with SCT PRP. when doing a in park rev log 1500,2000,2500,3000,3500,4000 rpm. I am in closed loop the STFT are within 3% and no matter what RPM the AFR is reading lean. While idling the Trims are perfect and AFR is around 17.2. If it was a air leak before the O2 it should go away with higher rpm but the inconsistency is the same. I am return fuel twin 340 in tank with Deka 80 40psi Base. My fuel injector data is correct. What can be doing this
STFT and AFR are way off
- Thread starter Lou02stang
- Start date
your wideband isnt reading correctly
you should set it for lambda btw but most likely need to wither calibrate it or get a new sensor
make sure its got a good ground too
btw the correct data for your injectors would have a high slope of 30
you should set it for lambda btw but most likely need to wither calibrate it or get a new sensor
make sure its got a good ground too
btw the correct data for your injectors would have a high slope of 30
I changed the Bosch 17025 sensor with a known good one and recalibrated it. Is my injector data wrong here
breakpoint— .0000241
Hi slope- .0208000
Lo slope- .0281000
Minimum pulse- .0005980
breakpoint— .0000241
Hi slope- .0208000
Lo slope- .0281000
Minimum pulse- .0005980
yeah thats wrong read my fuel write up
Ok I read your write up and I see in big red letters that Hi slope is single most important scalar. That being said on SCT the values are # per second. So according to your injector data hi slope for 80lb blue tip Deka is 75.157. So do I convert and use the 75.157 or like you previously mentioned 30. When 75.157 is converted to # per second that is currently the data I have in SCT. Thanks
Yeah you can't do that. You have to scale it.
The ecu cannot calculate an injector slope that high so you have to scale the tune.
keep in mind this has nothing to do with the wideband reading it has to be done regardless
The ecu cannot calculate an injector slope that high so you have to scale the tune.
keep in mind this has nothing to do with the wideband reading it has to be done regardless
so for Deka 80 blue tops do I scale 30# per hour or 75.157# per hour
in all eec's the high slope should always be 30 and that becomes your scaling percentage.
You cannot use 75.157 since the ecu cannot calculate that high.
high slope has to always be 30 / 3600 == 0.008333 lbs/sec
75.15 / 30 == 2.5052 is your scaling percentage.
You cannot use 75.157 since the ecu cannot calculate that high.
high slope has to always be 30 / 3600 == 0.008333 lbs/sec
75.15 / 30 == 2.5052 is your scaling percentage.
FYI my ECU strategy is CVAF1
So these will be the new values?
breakpoint .0000241/2.5052=.00000959
Hi slope- .00833
Lo slope- .0281000/2.5052=.0112
I didn’t see it in your write up so gonna ask to be sure. Does the Minimum pulse Width also get scaled by 2.5052
no the min pw, offset and deltap multipliers are unchanged but its good practice to always set minpw to 0 in all tunes regardless.
dont forget to adjust manifold volume engine displacement and the maf as well.
dont forget to adjust manifold volume engine displacement and the maf as well.
Thanks for the help it ended up being the Bosch O2's i switched to NTK and now STFT and LAMBDA on my gauge are in sync. Reading your fuel write up i converted to Return and kept the FRPS. Using SCT i cant find the switch to shut off injector compensation, in your write up you call it EFRS Adaptives Allowed SW. Do I Just populate all the multipliers with "1" then compensation will have no effect.
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Look under returnless fuel
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