P0172 GM Service Bulletin #18-NA-246 — TSB Fix

P0172 GM Service Bulletin #18-NA-246

GM has issued a service bulletin #18-NA-246 to address a P0172 code on the vehicles listed below.   This Bulletin applies to the vehicles that have fuel enriched engine oil due to short driving intervals.

 Vehicles affected by P0172 GM Service Bulletin #18-NA-246

Buick Envision 2016
Regal 2014-2019
Cadillac ATS 2013-2019
Cadillac CTS 2014-2019
Chevrolet Camaro 2016  -2019
Chevrolet Equinox 2018  -2019
Chevrolet Malibu 2013-2019
Chevrolet Traverse 2018-2019
GMC Terrain 2018-2019

All of the above vehicles equipped with the 2.0L LTG engine manufactured before May 7, 2019 or engine label T119127XHXTX0251. Decipher the engine label

The first digit reflects the engine plant (in this case T = Tonawanda).
The second digit reflects the shift (in this case 1 = First Shift).
The third and fourth digits reflect the calendar year (in this case 18 = 2018).
The fifth, sixth and seventh digits reflect the day of that calendar year (in this case 162 = 162nd day of 2018 calendar year (build date).

Cause of the P0172

If you drive for short intervals, excessive fuel may accumulate in the engine crankcase causing P0172 (Fuel Trim System Rich) enriched fuel conditions.

Fix for P0172 on 2019 vehicles

Review the date on the front engine cover. Vehicles built after May 7, 2019 already have the updated PCV installed. If your build date is before 19127 (May 7, 2019), EUN# T119127 XHXTX0251, you have the old PCV valve installed and it must be replaced.

Fix for P0172 on 2016-2018 Model Years:

Have the ECM reprogrammed with updated software

Replace the current PCV valve with the updated model (GM #55596783). Remove the valve cover and swap out the valves. Coat the seal on the new PCV with engine oil and press into place. Then perform an oil and filter change, clear the trouble code and test drive the vehicle.

©, 2020 Rick Muscoplat