Old school gearhead, but Newb to EFI tuning, trying to tune for boost with 80lb deka injectors using The Tuning school dodge book. Cant get rid of this surging at idle and low rpm cruise, and, if left in park the swings in rpm will almost always get progressively worse until engine stalls.
I don't believe it's vacuum leak, because I can load the old NA tune scaled to these injectors and will idle nice with little to no surging.
The way that the timing and rpms swing, remind me of hooking up distributor vacuum advance to manifold vacuum instead of ported vacuum..i.e. low rpm = high vacuum, advancing the timing, causing the rpms to climb, which results in less vacuum which retards the timing resulting in lowering the rpm, and it becomes a vicious cycle
help, please!
you could try bumping the numers down in your Throttle body model from .30 down and make sure you sync the numbers with your TBM and small and large range tables. Are you logging with an wideband AFR? your VE table could maybe use some tweaking? It looks a little off especially in the idle area. Also looking at your VE tables seems like you are running quite a bit of boost!
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