1971 PLYMOUTH SCAMP

Typical onset: 80,000-150,000 mi or age-related after 30+ years

Symptoms: Hard starting when engine is hot, Backfiring through carburetor, Loss of power and rough idle, Rattling noise from timing cover on startup, Check timing with light—if severely retarded, chain is stretched

Fix: Replace timing chain, gears, and tensioner. Front accessories must come off, harmonic balancer pulled, timing cover removed. Also replace oil pump drive shaft and inspect cam gear for wear. 4-6 hours labor for experienced tech. Replace front main seal while you're in there.

Estimated cost: $450-850

Symptoms: Hesitation on acceleration, Flooding and fuel smell in garage, High idle that won't come down, Stalling when coming to stop, Black smoke from exhaust (running rich)

Fix: Rebuild kit addresses worn throttle shafts, hardened accelerator pump, and deteriorated gaskets. If throttle shaft bores are wallowed out (common), body must be replaced or bushed. Most slant-six BBDs can be rebuilt in 2-3 hours; if replacement needed, expect 1 hour plus tuning time. Edelbrock conversions popular but require manifold swap on some years.

Estimated cost: $180-450 rebuild, $400-700 replacement

Symptoms: Front end sitting noticeably low, Uneven ride height side-to-side, Clunking from front suspension over bumps, Alignment won't hold—camber/caster drift, Rust visible at torsion bar anchors in rear crossmember

Fix: Torsion bars themselves rarely fail, but anchor points in K-member and rear crossmember rust out, especially in salt states. If crossmember is compromised, welding repairs or replacement required—serious structural work. Also inspect lower control arm pivot shafts for corrosion. Upper control arm bushings and ball joints typically need refresh by now. Complete front-end rebuild with structural repair: 8-12 hours.

Estimated cost: $800-1,800

Typical onset: 100,000+ mi or from repeated overheating

Symptoms: Vibration at idle in gear that disappears in neutral, Metallic rattling from bellhousing, Transmission overheating, Converter won't lock up properly—high stall speed, Transmission fluid contaminated with metal

Fix: Torque converter failure from flexplate cracking or internal fin damage. Transmission must be dropped, converter replaced, flexplate inspected for cracks (especially around bolt holes). If internal damage occurred, full rebuild required. Dropping 727 and R&R converter: 4-5 hours; with rebuild add 8-10 more hours.

Estimated cost: $600-900 converter replacement, $1,800-2,800 with rebuild

Symptoms: Intermittent gauge operation—fuel, temp, ammeter, Headlights dimming or flickering, No-start conditions that resolve mysteriously, Melted plastic smell from firewall area, Voltage drop across bulkhead connector terminals

Fix: Chrysler bulkhead connectors corrode internally and create high resistance. Pins can overheat and melt. Proper fix: remove connector, clean all terminals with contact cleaner and fine sandpaper, apply dielectric grease, reassemble. Chronic cases need terminal replacement or bypassing with weatherproof connectors. Also inspect ammeter circuit—high current through old connections causes failures. 2-4 hours diagnostic and repair.

Estimated cost: $150-400

Symptoms: Visible rust perforation in floor pans, especially driver's side, Rear spring perches rusting through trunk floor, Frame rail ends (torque box area) crumbling, Door alignment issues from body flex, Jack points collapsing

Fix: A-body unibody cars rust in predictable areas: front frame rails behind radiator support, rear leaf spring perches, floor pans under seats, and trunk drop-offs. Surface rust is manageable; structural rot requires welding in patch panels or full floor replacement. Inspect thoroughly before purchase—repairs are labor-intensive. Proper floor pan replacement with seam sealing: 16-24 hours depending on severity.

Estimated cost: $1,500-4,500