89 mustang mspnp2 surges in park

zinc4v

New Member
Nov 20, 2021
2
0
1
st.louis, mo
89 GT with stock heads and cam, performer rpm intake, 70 mm throttle body, on3 turbo, 50 lb injectors. Starts and drives pretty well. The issue I have is after it is warmed up it surges in park or neutral, in drive do not notice surging. A/F goes with surge, but have not had any success with modifying tables to correct. Attaching tune and log, any help would be appreciated.
 

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Turn off EGO correction at idle until you get this sorted, I personally leave my threshold at 1200rpm. Also shoot for a slightly rich idle, at least initially to make it less finiky. Shoot for 13.5-14.

The idle valve closed/open duty are set at 0/100, these values need to be set correctly.

You have drastic swings in the VE table in/near the idle cells, these transitions need to be cleaned up. The VE table in general needs alot of work.