The 1999 Buick Century has no open NHTSA recalls. Owners report 7 recurring issue clusters, led by “Intake manifold gasket coolant leak.” Buick uses the GM Oil Life System: an algorithm tracks engine revolutions and temperature, then lights the change-oil message — typically every 7,500 miles in mixed driving, capped at 12 months, using dexos-approved oil. Current Encore GX and Envista run 1.2/1.3L turbo three-cylinders where oil quality matters more than volume drivers expect (the sump is small and turbo-heated). Front-drive models pair to a CVT with a published fluid interval — it is not a lifetime part.
No open recalls on file. NHTSA lists no unrepaired safety recalls for this year, make and model. A recall can be issued at any time, and a specific car can still have one open — check yours by VIN at nhtsa.gov/recalls.
What drivers and federal regulators have officially reported about the 1999 Buick Century.
ENGINE AND ENGINE COOLING
40 NHTSA complaints · 2001-05 → 2015-05
“FAILURE OF INTAKE MANIFOLD GASKET ON 1999 BUICK CENTURY CAUSING ANTIFREEZE TO LEAK FROM MANIFOLD, LEAKING ANTIFREEZE INTO OIL”
“SECOND FAILURE OF INTAKE MANIFOLD GASKET ON 1999 BUICK CENTURY 3.1 M ENGINE”
“THE CONTACT PARKED THE VEHICLE AND A MECHANIC STATED THAT THE INTAKE GASKET WAS LEAKING COOLANT AND NEEDED TO BE REPLACED”
VISIBILITY
19 NHTSA complaints · 2002-10 → 2017-10
“A NYLON CLIP HOLDS THE TWO ENDS OF THE CABLING. THE PART BREAKS, THEN WINDOW DROP TO THE DOWN POSITION”
“WINDOWS JUST STOP WORKING PROPERLY THE WILL ROLL DOWN BUT NOT BACK UP”
“CONSUMER STATES 3 OF THE 4 WINDOW MECHANISMS BROKE WITHIN A MONTH OF EACH OTHER”
EXTERIOR LIGHTING
12 NHTSA complaints · 2000-02 → 2018-02
“THE VERTICAL HEAD LAMP ADJUSTING DEVICE MAY NOT BE CALIBRATED PROPERLY”
“CONSUMER STATED AFTER RECALL REPAIRS THE HEADLIGHTS BECAME DIMMER THAN BEFORE THE REPAIRS”
“THE RECALL REPAIR (99V-356) DID NOT RECTIFY THE HEAD LIGHT ILLUMINATION PROBLEM, CONSUMER IS STILL HAVING DIFFICULTY WITH VISIBILITY”
STEERING
7 NHTSA complaints · 2003-11 → 2017-10
“NOW WHEN TURNING LEFT THE POWER ASSIST FAILS, AND IT FEELS AS IF THE STEERING WHEEL IS LOCKED UP, BUT YOU CAN FORCE THE WHEEL FURTHER LEFT IF YOU TRY, BUT IT IS VERY HARD TO DO”
“WHENEVER THE CONTACT MAKES A LEFT TURN OR A U-TURN, THE STEERING WHEEL LOCKS AND BECOMES DIFFICULT TO TURN”
“WHEN THE DRIVER MADE A TURN IN EITHER DIRECTION THE STEERING BECAME DIFFICULT”
SERVICE BRAKES, HYDRAULIC
8 NHTSA complaints · 2007-05 → 2013-05
“BRAKE FAILURE, FRONT BRAKE LINE CORROSION (RUST THROUGH) RESULTING IN COMPLETE LOSS OF BRAKE FLUID”
“THE BRAKE LINES ON MY 1999 BUICK CENTURY CORRODED, FLUID LEAKED AND THE BRAKES FAILED”
“UPON FURTHER INVESTIGATION FOUND A BRAKE LINE RUSTED THROUGH”
AIR BAGS
10 NHTSA complaints · 2001-01 → 2015-02
“CONSUMER'S VEHICLE REAR ENDED ANOTHER VEHICLE AT 45 MPH, AND NONE OF FRONTAL AIRBAGS DEPLOYED”
“AIR BAGS DID NOT DEPLOY WHEN CAR HIT AND SHEARED OFF A TELEPHONE POLE”
“UPON IMPACT, AIR BAGS DID NOT DEPLOY”
VEHICLE SPEED CONTROL
10 NHTSA complaints · 2000-07 → 2010-02
“I PULLED INTO A PARKING SPACE ON A SLIGHT INCLINE AND WAS JUST RELEASING THE BRAKE PEDAL TO MOVE FORWARD WHEN THE CAR LUNGED VIOLENTLY FORWARD AS IF THE GAS PEDAL WAS TO THE FLOOR”
“CONSUMER WAS AT A STOP SIGN AT AN INTERSECTION WITH FOOT ON BRAKE, AND WITHOUT PRIOR WARNING, VEHICLE TOOK OFF, WENT INTO TRAFFIC, AND COLLIDED WITH ANOTHER VEHICLE”
“WHEN DRIVING ON HIGHWAY WITH CRUISE CONTROL ENGAGED AND WHEN ATTEMPTING TO DISENGAGE CRUISE CONTROL, IT WOULD NOT DISENGAGE, CAUSING UNWANTED ACCLERATION, VEHICLE CONTINUED TO GAIN SPEED”
Issues on other model years
Source: NHTSA Office of Defects Investigation (ODI). Complaint data refreshed Sep 20, 2026. Investigation data refreshed Sep 20, 2026.
We display NHTSA's record with attribution; we don't editorialize on what these complaints mean for any specific vehicle.
Critical for safety and preventing major damage
Change when the Oil Life System calls it — typically around 7,500 miles, never beyond 12 months. dexos1 0W-20 on modern engines. Small-displacement turbos (Encore GX, Envista): don't stretch the indicator.
Estimated cost — typical U.S. ranges
Dealer
~$120–$160
Shop
~$85–$115
DIY
~$25–$55
Full synthetic costs more than conventional. 5-quart 0W-20 + filter is the typical bill.
Rotate every 7,500 miles with the oil change — GM pairs the two in its schedule.
Estimated cost — typical U.S. ranges
Dealer
~$85
Shop
~$60
DIY
Free
Often free at the shop where you bought the tires — worth asking before paying.
Inspect pads, rotors, and lines at every service. Older Centurys: check rear drum adjustment and parking-brake cables, which seize with age.
Estimated cost — typical U.S. ranges
Dealer
~$85
Shop
~$60
DIY
Free
Most shops do this free as a courtesy with any service. Don't pay separately if you can avoid it.
FWD Encore GX and Envista use a CVT: GM schedules fluid replacement around 45,000 miles under severe service — which includes most city commuting. AWD Encore GX uses a 9-speed automatic instead (see transmission fluid).
Estimated cost — typical U.S. ranges
Dealer
~$360–$500
Shop
~$255–$355
DIY
~$80–$180
CVT fluid is manufacturer-specific and pricey — do NOT substitute conventional ATF.
Keeps your vehicle running smoothly and efficiently
Conventional automatics (Century's 4T65-E, Regal's Aisin, AWD Encore GX's 9-speed): GM lists 45,000 miles severe / longer normal. Older Buicks respond well to a simple drain-and-fill — avoid pressure flushes on high-mile units.
Estimated cost — typical U.S. ranges
Dealer
~$330–$500
Shop
~$235–$355
DIY
~$60–$180
Some sealed transmissions have no dipstick — fill is precise and best left to a shop. Many drivers can still DIY drain-and-fill.
Small-turbo three-cylinders (Encore GX, Envista): roughly every 60,000 miles — check the manual. Older 3.1/3.8 V6s: iridium plugs last to 100,000 miles.
Estimated cost — typical U.S. ranges
Dealer
~$285–$390
Shop
~$200–$275
DIY
~$25–$100
Iridium plugs cost more but last 100k+ miles. V6/V8 access varies wildly — some are tough.
GM schedules replacement around 45,000 miles; inspect at every oil change in dusty regions.
Estimated cost — typical U.S. ranges
Dealer
~$60–$95
Shop
~$45–$70
DIY
~$15–$40
5-minute job on most cars; the airbox lid usually has clips, no tools needed.
Inspect from 60,000 miles; replace on cracking or glazing rather than mileage alone.
Estimated cost — typical U.S. ranges
Dealer
~$195–$235
Shop
~$135–$165
DIY
~$20–$50
DIY-friendly if you can reach the tensioner. Inspect for cracks rather than swap on a strict mileage interval.
Extends the life of your vehicle and improves comfort
Replace roughly every 22,500 miles per GM's schedule — behind the glovebox on modern Buicks.
Estimated cost — typical U.S. ranges
Dealer
~$60–$95
Shop
~$45–$70
DIY
~$15–$40
Usually behind the glovebox. Shops charge labor for a 10-minute job — easy DIY win.
Dex-Cool is rated 5 years / 150,000 miles. On older 3.1/3.8 V6s, intake-gasket seepage was the classic failure — check coolant level and condition at every oil change on a Century.
Estimated cost — typical U.S. ranges
Dealer
~$285–$330
Shop
~$200–$235
DIY
~$25–$60
Use the manufacturer-specified coolant — wrong color/chemistry can damage the cooling system.
Test annually after year 3. Stop-start-equipped Encore GX/Envista use AGM batteries — replace like-for-like, not with a cheaper flooded battery.
Estimated cost — typical U.S. ranges
Dealer
~$225–$390
Shop
~$160–$280
DIY
~$130–$250
Most auto-parts stores test and install batteries free with purchase. Skip the dealer markup.
Occupant deaths in fatal crashes (FARS)
343 crashes 1990–2024
How the 343 occupant deaths break down
253
driver deaths
90
passenger deaths
343
occupant deaths
Crash years covered: 1990–2024 This model year first appears in 1998 crashes. Older models have had more years on the road to appear in these crashes, so a higher count here does not by itself mean a vehicle is less safe.
FARS counts every occupant death in a fatal crash, whatever the cause — it does not mean the vehicle was at fault or defective. Counts are not adjusted for how many of each vehicle are on the road. How to read this number
FARS 2024 data is an annual report file. NHTSA revises these records when the final file is published, so this count can change.
Every vehicle has exactly one driver seat, so driver deaths line up fairly when you compare one model to another. Occupant deaths include passengers, so a three row SUV can show a higher number than a two seat car simply because it carries more people.
Both figures are plain counts, not rates. A rate would need to know how many of each vehicle are on the road, and that registration data is not public, so we do not publish rates or scores of any kind.
IIHS publishes driver death rates using this same driver only idea, paired with a registered vehicle years denominator we do not have. Their rates and these counts answer different questions, so do not read either number here as a safety rating.
Owner-reported problem signals
Separate from the federal fatality data above: complaints owners filed with NHTSA about this year and model. These are reports of problems, unverified, and are counted here only as signals.
19
complaints mentioning a crash
4
complaints mentioning a fire
Typical U.S. ranges. Actual quotes vary by shop, parts choice, and vehicle condition.
How we estimate: Dealer = OEM parts × 1.4 + labor × $165/hr. Shop = parts + labor × $115/hr. DIY = parts only.
This maintenance schedule for the 1999 Buick Century reflects Buick's published service intervals and the GM Oil Life System system. Your actual service needs may vary based on driving conditions, climate, and vehicle usage. Always consult your owner's manual for model-specific recommendations.