The 2001 Buick Century with 3.1L V6 is an affordable, comfortable cruiser with a reputation for lower intake manifold gasket failures and transmission cooling issues. Budget for engine sealing and transmission service if buying high-mileage.
Lower Intake Manifold Gasket Failure (Dexcool-Related)
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: white smoke from exhaust on startup, coolant loss with no visible leaks, oil looks milky or chocolate-colored, engine overheating or misfires, rough idle when warm
Fix: Replace both upper and lower intake gaskets, flush contaminated oil, pressure-test cooling system. Also replace coolant elbows (plastic, brittle). 6-8 hours labor. If oil contamination was severe, expect shortened engine life—some need full rebuilds.
Estimated cost: $800-1,400
Transmission Oil Cooler Lines Leak at Radiator
Common · medium severityTypical onset: 80,000-150,000 mi
Symptoms: transmission fluid puddling under front of car, pink fluid mixing with coolant in overflow tank, transmission slipping or delayed engagement, engine overheating if coolant contaminated with ATF
Fix: Replace steel cooler lines (rust through at crimp fittings) and flush both transmission and cooling system if cross-contamination occurred. 3-4 hours labor. Contaminated transmission may need rebuild shortly after.
Estimated cost: $400-800 (lines only); $1,800-3,200 if transmission rebuild needed
4T65-E Transmission Torque Converter Shudder and Pressure Control Solenoid Failure
Common · medium severityTypical onset: 90,000-140,000 mi
Symptoms: vibration at 40-50 mph under light throttle, harsh or delayed 1-2 shift, slipping between gears, check engine light with P0741 or P0748 codes
Fix: Torque converter clutch wears out; pressure control solenoid also common. Often requires full rebuild or replacement. 12-16 hours labor for removal and rebuild.
Estimated cost: $2,200-3,800
Front Engine Mount and Transmission Mount Collapse
Common · low severityTypical onset: 70,000-130,000 mi
Symptoms: clunk when shifting into drive or reverse, excessive engine movement visible when revving, vibration at idle in gear, torque steer on acceleration
Fix: Hydraulic mounts leak and collapse. Replace front and transmission mounts together. 2-3 hours labor.
Estimated cost: $350-600
ABS Wheel Speed Sensor Corrosion
Occasional · medium severityTypical onset: 80,000-150,000 mi
Symptoms: ABS light on, traction control disabled, codes for front wheel speed sensors, normal braking works but no ABS assist
Fix: Rear sensors mount in hub and corrode or crack wiring. Fronts are integral to hub bearing assembly and require full hub replacement. 1.5-2 hours per side.
Estimated cost: $200-350 per rear sensor; $400-700 per front hub assembly
Fuel Pump Failure
Occasional · high severityTypical onset: 100,000-160,000 mi
Symptoms: no start or long crank before starting, stalling when fuel tank below 1/4, loss of power under acceleration, whining noise from rear of car
Fix: In-tank pump assembly. Drop tank, replace pump and strainer. 3-4 hours labor.
Estimated cost: $500-850
Buy only if under 80,000 miles with documented intake gasket replacement and regular transmission service—otherwise, you're inheriting expensive repairs within a year.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.