3-second answer: Coolant smell + wet passenger carpet + no heat = **heater core**. The factory job pulls the dash (~6-8 hours). The community shortcut: cut an access panel in the plenum under the hood, or (on many trucks) work through the glovebox opening with the core split — many guys do it without a full dash pull. Set aside a weekend either way.
Symptoms
- Sweet antifreeze smell inside
- Passenger-side carpet wet or stained
- Fogged windshield that won't clear
- No heat (coolant never reaches the core)
Confirm before you commit
Pressure-test the cooling system and check the heater control valve (if equipped) and blend door first — a stuck blend door mimics a dead core for $2 in parts. Also check the quick-connect fittings on the firewall: they leak with age and trick people into thinking the core is gone.
The job
- Drain coolant (or use the two firewall shutoff valves trick to save most of it).
- Disconnect the two heater hoses at the firewall.
- Remove the dash (full method) OR cut/access the plenum (shortcut method — check your year; the plenum layout varies).
- Replace the core, reinstall, bleed, and verify heat.
Parts
- Heater core: ~$40-80 (Spectra/aftermarket are fine)
- Hose kit + clamps while you're in there
- New plenum foam/seal — cheap, worth it
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Threads
- FTE search: heater core · no heat