What are the most common Buick LeSabre problems?
According to Au7o's research across NHTSA recalls, manufacturer TSBs, and owner forum reports, the 1999 Buick LeSabre has 6 documented issues. The most frequently reported are: In-Tank Fuel Pump and Fuel Level Sender Failure (Stalling, No-Start, Erratic Gauge), LeSabre 3800 V6 Lower Intake Manifold (LIM) Gasket Leak, Fuel Pressure Regulator Diaphragm Leak — Fire Risk Recall (NHTSA 04V090000 / GM 03054B). Of these, 4 are rated critical and should be addressed promptly.
Is the Buick LeSabre reliable?
The 1999 Buick LeSabre has 6 known issues compiled from NHTSA recalls, manufacturer TSBs, and owner forum reports. 4 issues are rated critical: In-Tank Fuel Pump and Fuel Level Sender Failure (Stalling, No-Start, Erratic Gauge) and LeSabre 3800 V6 Lower Intake Manifold (LIM) Gasket Leak and Fuel Pressure Regulator Diaphragm Leak — Fire Risk Recall (NHTSA 04V090000 / GM 03054B) and Plastic Upper Intake Manifold (Plenum) Degradation Causing Coolant Leak and Hydro-Lock Risk. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Buick LeSabre problems?
Repair costs for known Buick LeSabre issues range from $100 to $1,200, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, In-Tank Fuel Pump and Fuel Level Sender Failure (Stalling, No-Start, Erratic Gauge), typically costs $400-$800 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 1998-2005 Buick LeSabre In-Tank Fuel Pump and Fuel Level Sender Failure (Stalling, No-Start, Erratic Gauge)?
The in-tank fuel pump module on these LeSabres is a common high-mileage failure: the pump weakens or overheats and dies, causing sudden stalling at speed or a crank-no-start, while the fuel level sensor on the same module wears and makes the gas gauge read erratically or stick. N… Repairs typically run $400-$800. Severity: high.
What is the 1995-2005 Buick LeSabre LeSabre 3800 V6 Lower Intake Manifold (LIM) Gasket Leak?
Same 3800 V6 LIM-gasket failure mode as Park Avenue — extremely widespread in 1995-2005 LeSabres. Coolant migrates past degraded plastic-and-rubber gasket into the valley, contaminating engine oil. Owners commonly first notice low coolant with no visible leak; by the time milky o… Repairs typically run $400-$1,200. Severity: high.
What is the 1998-2000 Buick LeSabre Fuel Pressure Regulator Diaphragm Leak — Fire Risk Recall (NHTSA 04V090000 / GM 03054B)?
Delphi fuel pressure regulators on 1998-2000 LeSabres with the 3800 V6 (L36) had an abnormally high rate of diaphragm leaks that let raw fuel be sucked into the intake manifold through the vacuum line. During a slow-crank start, the fuel-loaded manifold can backfire violently eno… Repairs typically run $100-$300. Severity: high.
What is the 1996-2005 Buick LeSabre Plastic Upper Intake Manifold (Plenum) Degradation Causing Coolant Leak and Hydro-Lock Risk?
The naturally aspirated 3800 Series II V6 (L36) uses a composite plastic upper intake manifold whose material degrades around the hot EGR stovepipe passage. Over time the plastic erodes and cracks, letting coolant leak externally near the throttle body or internally into the inta… Repairs typically run $450-$950. Severity: high.
What is the 1992-2005 Buick LeSabre PASS-Key Anti-Theft System Fault — Security Light On, Engine Cranks but Won't Start?
The factory anti-theft system (PASS-Key resistor-pellet keys on 1992-1999; PASS-Key III transponder keys on 2000-2005) is a frequent no-start culprit on aging LeSabres. Worn contacts in the ignition lock cylinder, broken sensor wires in the steering column, or a worn key pellet m… Repairs typically run $200-$600. Severity: medium.
What is the 1992-2005 Buick LeSabre Electronic Climate Control Programmer / Blower Control Module Failure?
LeSabres with automatic climate control rely on an HVAC programmer (1992-1999) or a blower control module (2000-2005) instead of conventional relays and resistors, and these electronic controllers are a well-documented failure point. Heat ages the module's electronics and the pro… Repairs typically run $150-$500. Severity: medium.
