Red = AFR
Greed = RPM
Blue = MAP

Well I really need some professional input on this one. I have tuned every load bar on up to 15psi yet I get this lean spot that occurs only as the boost is rising (right after hitting WOT). It stays lean until the map hits 10psi (max boost right now) and then holds a steady afr. I have tried increasing the throttle pumps but that only enrichens while the throttle is moving (on the E8). This lean spot is after the throttle has hit 100% (0 psi) and the boost starts rising. Total time is about 1sec but that scares me to see 14afr. I have tuned this area to be much richer than that so this really has me stumped

BTW, I upgraded the vaccuum line to the map sensor and drilled out for a larger port in the manifold to cut down on any restriction the line might of had. It's only about 10in long and almost 3/8 dia.

 

Damn, I guess nobody has an answer to this one :-(
My theory is that it's the transition from pri to pri+sec that's causing it to go lean. I wish I could increase throttle pump sustain but my E8 doesn't have that feature. All the throttle pump settings are in one window under injector setup. That's it.
Running 1.71 software. Anybody else have sustain/decay setting?

 

could it be raw fuel hitting the sensor (too much fuel) causing it to read lean? or like u said maybe the transiation of the injectors.

 

Did I read the pic right?
You're trying to tune boost ranges under 2,000RPM???


-Ted

 

If its occuring at the same MAP values everytime, its a transition issue.

What boost are you seeing 14AFR's? I run a little lean in the ramp up areas...13.0-12.8 up to about 4psi (just after staging)

But just watch where its happening every time, I know there's alot of features for staging on the E8 like primary hold etc so you should be able to makea good transition - although I've got limited experince with that ECU.

 

Another thread about leanspots?! Try playing with your Throttle Pumps!

 

Yes, yes, of course I have. But that only injects fuel for the short time the throttle is traveling to 100%. The lean area occurs directly afterwards. I am going to try the new 1.89 software and see if I can get any control over TP decay.