Polarity

[walela1]

Anyone know the proper procedure for polarity checking on the ignition coil connectors? I had the GMS cops, and went back to the OEM units after the loose sparkplug incident described in a previous post, and hopefully changed all of the connectors back to factory polarity.

Reason I ask due to still having some vibration between 1500-2000 RPM, I will still change all of the plugs this weekend, ( 38K on originals, DR tune onboard so going to NGK TR55s.) But if that does not correct the problem, I am at a loss. Another forum member suggested it may be trans related, and @ 38K mine is overdue, could that be what I am experiencing?

:help:

[Stranger in the Black Sedan]

I would be highly doubtful of a trans fluid change interval being narrowly missed, causing vibrations.

[gdmjoe]

walela1 ... Reason I ask due to still having some vibration between 1500-2000 RPM ... Another forum member suggested it may be trans related, and @ 38K mine is overdue, could that be what I am experiencing?
If that 1500-2000 RPM vibration occurs usually during the shift to OD under light acceleration and feels like you're briefly traveling a wash-board road, it could be the infamous torque converter shudder that usually occurs @ ~25-35000 miles.

A transmission flush cured mine.
.