Huge lean spikes from oem 2ndary tbody blade opening...help?

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mxmang
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Huge lean spikes from oem 2ndary tbody blade opening...help?

Post by mxmang »

MS2 v3 stock coil igbt.. vw 2L 16v... firmware 2.33 or 2.35? megatune 2.25

Hey boys, i had a bunch of missing issues, i tracked it down to lean condition spiking as high as 25:1 when the secondary tbody blade opens.... (this car has a small and then a big opening) it kicks in around 25-30% throttle i think... but the map goes from like 35-40kpa to like 60-70 kpa instantly... so its almost confusing to the ecu... i tried richening up my bins in the ve table they are almost 75-80 in the 40-70 kpa 2000-5500 range maybe higher... but its still running like poop... if i turn the acceleration dwell to .8 instead of 1 its a bit more bearable... i didnt have this problem before when i just loaded these maps (from another vw guy with a similar setup)

Should i be cranking my required fuel? I was told to tune the ve with the acceleration enrichment off... i tried that, i coudlnt even drive the damn thing... i think my accel bins are as tehy came liek 150 120 99 80 or something... should i set my slider all the way to TPS or MAP ? should i lengthen the ammount of time for each accel enrichment bin? is there a setting i shuld play with below in the lower boxes?

I would appreciate this, it makes driving to work a pain in the butt!

-Dale :)
Fastest95PGT
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Post by Fastest95PGT »

Some vehicles do not run very well at all (if even drivable) with the accel enrichments turned off so you are not alone.

You could just tweak your VE to make up for the lean spike, but this would only work if the second butterfly is triggered by MAP, not TPS as you described.

I don't run MS2 and haven't looked at it's options, but MS1's MSnS-E has the ability to use MAP for your accel enrichment trigger as opposed to TPS. If MS2 has this ability, I would suggest looking into it.
1995 Ford Probe GT ~ Megasquirted & Boosted
275whp/242wtq @ 5.5psi ---- 317whp/287wtq @ 8.5psi
^^^ (thanks to MSnS-E and dyno tuning by me!)
2003 GSX1300R (Hayabusa)
mxmang
MegaSquirt Newbie
Posts: 9
Joined: Sat May 27, 2006 3:56 am
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Post by mxmang »

an update, i loaded the ms2 default afr target table from the "tuning your megasquirt " page, set the ego authority to 11% and it seems to be bringing the spike to aroung 18:1 and i cant erally feel it anymore most times.....

some good news, my duty cycle is hitting 70% as a max under alot of load and during spikes so prolly more like 60-65%... so, shuold i just maybe turn my req fuel up ? i have to give my car a tiny bit of fuel to start anyways when its cold...

thanks!
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