EFIDynoTuning Forum

Hi, I removed T4M2 Decel Spark Table patch and set the table all to 60. All other DFS0 scalars were set to what usually works for me on decel, but I get no decel fuel cut off with this tune. At Idle, timing stays at min clip of 10 degrees (spark source = 8) until I press the go pedal. I have dug into the tune and found some DFSO differences from stock T4M2. I tried a few changes, but no glory yet. Have not yet found anything that makes timing clip to SPK_FBS_MIN. Any suggestions?

spark and dfso are two different unrelated entities

one of the dfso parameters is preventing it then. Verify the temp and min delay scalars arent too high.

if idle spark is clipped at min then verify rpm isnt above dsdrpm.
Usually that happens when the throttle stop is too far open.

I was looking at this and found the following. TunerPro won't allow a change to this. It does say "max", but could this be any part of my idle spark issue?

nope

I thought I'd follow up on this. I had set FN2000 / 2000D table to all zeros, and set the 2000D Cold Spark Max CT Switch to 1, however I did not set the FN2001 table to a high value (63.75 is stock, T4M2 is all zeros). This had the system clipping to min spark at idle which was set at 10 degrees BTDC. I assume setting FN2000 / FN2000D table to all 60 or so, and leaving the Cold Spark Max Clip Switch and FN2001 table at all zeros would do the trick as well, if someone chose not to use this start up spark modifier.

All said and done, I set the FN2000 / FN200D table, FN2001 table, and 2000D Cold Spark Max CT Switch to the original T4M2 settings. That works fine too.

The DFSO is also working fine now. I don't recall what I did for the DFSO right now. It's been a few days since.

Its not wise to change any of that.

Its set like it is to have timing reduced at startup to prevent start up knock, reduce emissions, heats up the o2s faster and forces more air for greater idle stability and more torque reserve.