Mark,

I had a similar problem when trying to tune the fuel mixture table after installing the snubbers.  I don’t have a firmware change related to the snubbers, so my situation isn’t as similar to yours as it could be.  For some reason, my injector staging threshold got set to 12 in Hg MAP.  I probably made the change myself unintentionally.  Staging at this low a MAP was not satisfactory because using all four injectors at that low a fuel flow rate was not reliable with symptoms very similar to yours.  Changing the staging threshold back to around 16 in Hg allowed successful map table adjustments although it took some work to get the staging to go smoothly at the higher threshold.  Verifying your staging threshold might be a good thing to check.  If you’ve already done this, hitting the delete key would be an appropriate response to this email.

Steve Boese