7.3 Godzilla (gas): misfire, rough idle, hesitation or surging

3 documented failures on this engine list this among their signs. They are ordered from the most widespread down. Each one shows the signs in its record's own words, how to tell it from the others, the usual fix and any recall or bulletin.

Cam lobe and lifter (tappet) wear, worst with long idling Common · 13 complaints · 1 recall/bulletin
Ignition service wear (plugs / coils) Common
Broken valve springs (sudden single-cylinder misfire) Occasional

Not sure which engine you have, or want the recalls for your exact truck? Check your VIN: it names the engine and lists the campaigns for that model year. Whether a recall is still open on your VIN: nhtsa.gov/recalls.

1 Cam lobe and lifter (tappet) wear, worst with long idling

verified How widespread: Common 13 NHTSA owner complaints match it, out of 58 checked

How it shows up

tapping noise that progresses to a misfire on one cylinder and a rough run
check engine light / misfire codes (P0300-P0308), sometimes a flashing light under load

Its other signs

metal in the oil filter; owners report engine replacement once metal has circulated

How to tell it apart

locate the noise: lower front at the timing cover/oil pan seam on 2020-2022 = check the oil pump drive gear first (SSM 50830/51330); top end and following one cylinder = lifter/cam
read misfire counters; a misfire that follows the cylinder (not the coil or plug) points to the valvetrain
cut the oil filter: metal means the cam/lifter damage has circulated

Usual fix

replace collapsed lifter(s); inspect the corresponding cam lobe - a flaked lobe means cam replacement, not just the lifter

Recalls and bulletins

Ford 24B27 (and supplements S1-S3)

Root cause, parts and sources →

2 Ignition service wear (plugs / coils)

aggregated How widespread: Common

How it shows up

gradual roughness, longer crank, misfire codes at service mileage

Its other signs

coils fail individually with age/heat

How to tell it apart

pull plug condition at service mileage; replace as a set on an aged engine
test coils on a miss before replacing hardware in bulk

Usual fix

service: plugs + coils as wear parts; keep plug wells sealed

Root cause, parts and sources →

3 Broken valve springs (sudden single-cylinder misfire)

aggregated How widespread: Occasional

How it shows up

sudden rough running / flashing misfire light on one cylinder, often at speed
compression miss that follows the cylinder, not the coil or injector

Its other signs

cited on owner forums; not one NHTSA complaint on 2020+ gas Super Duty trucks names a valve spring (checked 2026-10-14)

How to tell it apart

confirm the miss follows the cylinder: swap coil and plug across cylinders or use relative-compression test
leak-down / compression test on the dead cylinder before pulling the valve cover
inspect the spring hardware on the dead cylinder and, on a high-mileage engine, consider surveying the rest

Usual fix

replace the failed spring(s) with updated hardware; on a high-mileage engine survey remaining springs

Root cause, parts and sources →

Other symptoms on the 7.3 Godzilla (gas)

Hard start, long crank or no-start Ticking, knocking, rattle or whine

Everything on the 7.3 Godzilla (gas)Its recalls and bulletins

Order: how widespread each failure is in its record (near-universal, very common, common, occasional, rare), then the number of NHTSA owner complaints that match its keywords. Complaint counts are keyword matches, not a manual review of each complaint. A symptom listed here means the failure is documented with that sign; it is not a diagnosis of your truck. Tiers: verified, aggregated, contested, data-gap. How we tier and source facts.