1991 PONTIAC GRAND PRIX

Symptoms: clunking over bumps, steering wander or instability, visible rust perforation on subframe rails, control arm mounts separating from cradle

Fix: Complete subframe replacement requires dropping the entire cradle, which means supporting the engine, disconnecting steering rack, control arms, and exhaust. Expect 8-12 hours labor at a shop with a lift. Many rust-belt examples are beyond economical repair.

Estimated cost: $1,200-2,500

Typical onset: 80,000-120,000 mi

Symptoms: coolant loss with no external leak, white smoke at startup, rough idle when cold, oil looks milky or has coolant mixed in

Fix: The plastic intake gaskets deteriorate and allow coolant into the crankcase or out the back of the engine. Requires upper plenum removal, new gaskets, and often new coolant elbows. 4-6 hours labor. Do the valve cover gaskets while you're in there.

Estimated cost: $600-900

Typical onset: 90,000-140,000 mi

Symptoms: fluid pooling under front center of car, groaning or whining when turning, heavy steering feel, steering wheel not returning to center

Fix: Rack seals fail and inner tie rod boots tear. Rack replacement requires dropping the subframe or extensive disassembly from below. 5-7 hours labor. Use OEM or quality rebuilt units; cheap racks fail within a year.

Estimated cost: $700-1,200

Typical onset: 70,000-110,000 mi

Symptoms: check engine light for evap codes, fuel smell after fillup, difficulty filling tank or pump nozzle clicking off repeatedly, hissing when opening gas cap

Fix: Pressure relief valve in tank or vent solenoids fail. Sometimes just a new gas cap; worst case requires tank drop for valve replacement. 2-4 hours if tank comes down. Related to recall for fuel tank pressure devices.

Estimated cost: $150-500

Typical onset: 80,000-130,000 mi

Symptoms: intermittent no-start, dash lights flickering, battery repeatedly dying, gauges going haywire, multiple electrical accessories failing at once

Fix: CS130 alternators wear out and the underhood fuse block corrodes due to poor seal design. Alternator is 1.5-2 hours; fuse block cleaning or replacement adds 2-3 hours if corrosion is severe. Check both if you have weird electrical issues.

Estimated cost: $300-700

Typical onset: 60,000-90,000 mi

Symptoms: overheating, coolant loss, rough running, misfires on one bank, oil in coolant or vice versa

Fix: The 3.4L twin-cam is an interference engine with a timing belt that MUST be changed every 60k. Head gaskets fail when overheated. Belt job is 4-5 hours; head gasket work is 12-16 hours because of the transverse layout and tight engine bay. Not a DIY-friendly engine.

Estimated cost: $800-1,200 for timing belt; $2,000-3,500 for head gaskets

Symptoms: soft or spongy brake pedal, visible rust perforation on steel lines along frame rails, brake fluid leaking near rear axle or along underbody, brake pedal going to floor

Fix: Factory steel brake lines rot out, especially rear lines and those running along the subframe. Complete line replacement (all four corners) is the right fix. 6-8 hours labor with pre-bent line kits; custom bending and flaring adds time. Safety-critical repair.

Estimated cost: $600-1,000