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Recipe - Ram 6.4L HEMI Gasoline (Ram HD 2019+)

Reliability build

Reliability tier: verified - verify before ordering, see /disclosure/

Ignition service for the 6.4L HEMI (mode Ignition service wear (plugs / coils)): 16 plugs on the OHV V8, one coil per cylinder, MDS runs under the covers. Rough idle and flashing MIL trace to plugs at the interval or a failed coil - swap-test before buying.

Parts

• 6.4L HEMI Spark Plug (OEM) - spark plug, one per cylinder (SP138239AC) (qty 16)
• 6.4L HEMI Ignition Coil (OEM) - ignition coil, swap-test suspects (68238603AA) (qty 1)

Install order

1. read misfire counters; map the dead cylinder(s)
2. swap-test the suspect coil to a good cylinder
3. renew all 16 plugs at the interval; dielectric on the boots

Expected outcome

Clean idle, no misfire counters.

Do not

• do not chase a random misfire with coils alone - check plugs and injectors first

Parts budget

About $110-$320 in parts. It depends on what the diagnosis finds; each option below is what you buy together. Prices marked "at Dave's" are Dave's Auto Center's, the same as in his store; the others are approximate prices from OEM and maker catalogs, rounded (a manufacturer's list price can run higher). Parts only, no labor.

• about $320: 16 × 6.4L HEMI Spark Plug (OEM) (about $20)
• about $110: 6.4L HEMI Ignition Coil (OEM) (about $110)