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Scanner RPM has lost it's mind!
I have a new build with about 25 miles on it so far. Was having an erratic stalling issue that I tracked down to a bad coolant sensor. After replacing that sensor I started the engine and monitored the warmup cycle. Everything was looking fine and then all of a sudden the Engine RPM in VCM Scanner started seeing these wild swings in RPM. Engine is sitting there purring at 800RPM (factory tachometer works fine in the truck), but Scanner is saying 2500, then 9000, then 10,000, then 3000. It's absolutely all over the place, even though the engine is just sitting there idling smoothly.
Has anyone seen this before? I tried the Crank Relearn Procedure, but it did nothing to fix the issue. Crank is new, but cam is same as I've had for years. The PCM must have an accurate RPM signal since the engine is running just fine, but for some reason the Scanner is reporting a crazy number.
Also tried disconnecting VCM, disconnecting/reconnecting MVPI, rebooting laptop, starting the process all over again. Reloaded the tune. Did Crank Relearn Procedure. Let the truck sit overnight, let it sit for a week, etc. No matter what I do now when I connect and start the engine the engine RPM is completely inaccurate.
This was a build that was working fine for years with same OS (2bar OS) and a similar tune until I pulled the engine to rebuild it after a catastrophic valvetrain failure. Most sensors are the same as what was in the truck before I pulled engine and it was working fine. Hopefully someone has had this issue before and it's something simple.
