Rough Running Ram

July 30, 2021
This bulletin applies to 2015-2018 RAM ProMaster City vehicles.

This bulletin applies to 2015-2018 RAM ProMaster City vehicles. Customers may experience a MIL on. The technician may find one or more DTCs set: 

P0300 (multiple cylinder misfire)

P0301 (cylinder 1 misfire)

P0302 (cylinder 2 misfire)

P0303 (cylinder 3 misfire)

P0304 (cylinder 4 misfire)

Some customers may also experience a rough running engine. One cause may be faulty ignition coil boots. Clean the area around all coils to prevent debris from falling into the plug wells. Remove the ignition coils. Remove the boot(s) from the coil(s). The boot seat on the coil bottom flange should be free of debris. If contaminated, clean the surface with a clean rag. Use parts cleaner MOPAR 04318040AC to prepare the surface of the coil. Use at air temperature and allow to dry. Apply the supplied label to the coil side. Ensure that the spring is inside of each new boot.

Assemble the new boot onto the coil, pushing and turning until fully seated. Place a small 360-degree bead of MOPAR Molykote G-5008 lubricant along with the inside opening of the coil boot, about 1/32 to 1/16-inch from the chamfer edge, but not on the chamfered surface. Chrysler notes that this Molykote grease is the only grease that should be used. The use of other grease may cause boot damage over time. A new bootkit is available as P/N 68420587AA.

Reinstall the ignition coils. Clear faults. Start the engine and allow it to run for at least 60 seconds. If the engine runs rough and/or the check engine light illuminates, further diagnosis will be required.

About the Author

Information courtesy of Mitchell 1

Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.

About the Author

Mike Mavrigian | Motor Age Editor

Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of  specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.

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