Weird fuel tri.s

[Sting_em]

Im getting weird fuel trims, no matter what map the trims spike high then drops way down at higher rpm. Thanks for the feedback

 

[Thomby]

BMS says expected values for fuel trims are a spike to mid-40s at peak torque, then a taper down to around 25 (no adjustment, I believe) by upper revs / peak power. I don't have my full excel view here but it looked like you were seeing a similar trend (think I saw a 50, but you're in map 4 running E30, I assume, so maybe needing a bit more at peak demand).

 

[Sting_em]

Im running closer to e45 since I can only get 91 around me. But thanks for the info. Just seems like more demand up in higher rpms. Or if I had a possible vacuum leak. Everything in my logs look good then?

 

[Thomby]

Im running closer to e45 since I can only get 91 around me.

That's good from an octane/knock standpoint (your "ign" values, which are timing pulls, are clean), but would also increase fuel demands. But the trims look normal to me, and your high pressure (fp_h) never drops below 10 so I don't think it's an issue.

"E30" is really just a guideline that works for most of our cars, providing enough octane increase (and cooling etc) to run higher boost without hitting the HPFP limits, but it's not a super sensitive value. So E28, E36, etc are typically fine, and some guys have pushed it to E40-E50, you just have to be aware you're closer to the car's limits.