This service bulletin provides guidelines and diagnostic/repair information to technicians regarding vehicle engine oil consumption.
full bulletin at NHTSA ↗2006 Cadillac STS engine problems
severe Owners of the 2006 Cadillac STS have filed 18 NHTSA complaints about the engine, typically surfacing around 76,663 miles at roughly $3,100 to repair (U.S. federal records, as of August 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Failure mileage
Complaints
18
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2005 STS | 12 |
| 2006 STS (this page) | 18 |
| 2008 STS | 8 |
2crashes
1fire
4injuries
When does it fail?
Of the 18 engine complaints filed for the 2006 Cadillac STS, here's the actual mileage breakdown — failures cluster heaviest at 25,000-50,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
No new NHTSA engine complaint has been filed on this vehicle in over 11 years — the issue may be aging out of the active population.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This service bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
full bulletin at NHTSA ↗This technical bulletin advises of a new fuel injection cleaner kit used for decarbonizing the intake valves to correct conditions of rough idle, Crank no start, extended crank or misfire, MIL with DTCs, and explains how Top Tier fuels should be used to reduce carbon build-up.
full bulletin at NHTSA ↗This service bulletin provides service information to technicians on guidelines to replace Oil Cooler, Oil Cooler Lines and Oil Tank if the engine was replaced where large amounts of debris has flowed throughout the oiling system.
full bulletin at NHTSA ↗This Warranty Admin service bulletin provides guidelines for Dealers Not Required and for Dealers Required to Contact the PQC for engine or transmission assembly replacement and explains the PQC process, GWM Transaction submission, vehicle service record retention and proper handling of assembly returns for Canadian Dealers only.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners report multiple engine failures that go beyond normal wear. A rocker arm broke at 83,000 miles on a dealer-maintained vehicle, requiring a $12,678 engine replacement after debris scored the cylinder—the owner notes the vehicle was only 11 years old at the time. Several owners describe sudden, complete engine stalls while driving at highway speeds (45–70 mph) with no warning, resulting in total loss of power steering and power brakes—one stall caused a crash into a tree with injuries. One vehicle reversed at high RPM with the engine in Park and emergency brake on, hitting a parked car and a building.
Fuel delivery problems are widespread: vehicles refuse to start after refueling until multiple attempts, and hesitate dramatically on the highway, creating dangerous speed loss. Owners reference a recall (NHTSA 14V542000) that parts suppliers couldn't fulfill. The timing chain stretches prematurely—one stretched at 53,820 miles, another at 76,663. Catalytic converters fail repeatedly; one owner replaced one at 83,000 miles and got another code at 93,000 miles in the same car. A vehicle caught fire in the driver-side door panel while parked. Misfires, spark plug failures, excessive oil consumption, and ignition problems round out the complaints. One owner reports the check engine light staying on for two years with recurring cold-weather stalls.
Same Cadillac STS engine reports on nearby years: 2005
Failure modes owners describe
Rocker Arm Breakage
Rocker arm fractured at one cylinder, debris fell into combustion chamber causing valve seat and piston scoring. Engine no-start condition resulted.
When: 83,000 miles
Symptoms owners cite: engine miss/misfire; inability to restart after shutdown; loss of power assist on brakes concurrent with engine miss
Repairs/costs cited: Engine replacement with remanufactured unit; $12,678.25, 6 weeks to complete
Fuel System Delivery Failure
Fuel pump or fuel delivery system fails to supply adequate fuel after refueling, requiring multiple start attempts. Highway hesitation and dramatic speed drops reported. Multiple owners reference recall NHTSA 14V542000; parts were unavailable.
When: varies; noted at 100,000+ miles for some vehicles
Symptoms owners cite: no-start condition after refueling until multiple start attempts; highway hesitation and sputtering; dramatic loss of speed while driving
Repairs/costs cited: Dealership unable to perform recall repair due to parts unavailability
Recalls/TSBs owners mention: Recall NHTSA Campaign 14V542000 (Fuel System, Gasoline) issued; parts availability uncertain per manufacturer
Timing Chain Stretch
Timing chain stretches, triggering check engine light and loss of engine performance. Requires replacement.
When: 53,820 miles; 76,663 miles in separate report
Symptoms owners cite: check engine light illumination; loss of power
Repairs/costs cited: Timing chain replacement performed in one case; not repaired in another
Catalytic Converter Failure
Catalytic converter fails prematurely, triggering check engine light. Multiple failures within same vehicle reported. GM recalls 2005 models but not 2006.
When: 83,000 miles on first failure; 93,000 miles on recurrence in same vehicle
Symptoms owners cite: check engine light illumination; loss of power on acceleration; hesitation and sputtering
Repairs/costs cited: Converter replacement performed; failure recurred at 93,000 miles
Recalls/TSBs owners mention: GM recall exists for 2005 model; 2006 model not recalled
Complete Engine Stall While Driving
Engine stalls without warning at highway and city speeds, resulting in total loss of power steering, power brakes, and all electrical accessories. Safety-critical function loss during operation.
When: 60,000 miles; 45 mph incidents; 70 mph incident; intermittent at 84,000 miles
Symptoms owners cite: sudden engine stall without warning; complete loss of power-assisted steering; complete loss of power-assisted brakes; loss of all accessories and lights; vehicle unable to be controlled
Repairs/costs cited: One crash into tree with injuries; one unrepaired stall incident; one no-repairs-performed ignition problem diagnosis
Unintended Reverse Acceleration in Park
Vehicle accelerated in reverse at high RPM while in Park with emergency brake engaged, engine making loud whining noise. Resulted in collision with parked car and building impact.
When: unknown mileage
Symptoms owners cite: high RPM acceleration without operator input; loud whining noise from engine; vehicle moved in reverse while in Park with emergency brake on; brake pedal went to floor without effect
Repairs/costs cited: Vehicle involved in collision; brake failure concurrent with engine acceleration event
Engine Fire in Door Panel
Vehicle caught fire in driver-side door panel while parked in parking lot. Vehicle totaled.
When: unknown mileage, parking lot incident
Symptoms owners cite: fire originating in driver-side door panel
Repairs/costs cited: Vehicle totaled; fire department response required
Ignition/No-Start Problem
Vehicle fails to start or stalls when exposed to cold weather; intermittent stalling and no-start condition recurring over time.
When: 84,000 miles; recurring from March 2007; intermittent failures after refueling in separate case
Symptoms owners cite: failure to start in cold weather; stalling and no-start conditions; recurring intermittent stalls
Repairs/costs cited: One accessory light illumination concurrent with stall, ignition problem suspected but not repaired; check engine light on for 2 years in another case
Misfires and ICM Failure
Eight engine misfires detected; Ignition Control Module (ICM) diagnosed as faulty. Replacement performed but misfires recurred.
When: 96,000 miles
Symptoms owners cite: eight engine misfires; check engine light illumination; recurring misfires after ICM replacement
Repairs/costs cited: ICM replacement performed; failure recurred
Spark Plug Failure
Spark plugs fail repeatedly, causing clicking noise in cylinders 1 and 3.
When: unknown mileage
Symptoms owners cite: clicking noise from engine; spark plug failure affecting cylinders 1 and 3
Oil Consumption Excessive
Engine consuming oil at high rate. Over 1 quart missing one week after synthetic oil change; up to 4 quarts missing at times. Concurrent with fuel system issues reported in same vehicle.
When: unknown mileage
Symptoms owners cite: oil level dropping rapidly between service intervals
Axle Seal Fracture
Front passenger-side axle seal fractured, causing oil leak and burning odor inside vehicle.
When: 120,000 miles
Symptoms owners cite: strong burning odor inside vehicle; oil drops visible on ground
Repairs/costs cited: Diagnosed but not repaired by owner
Synthesized from 18 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 2 most recent
The fuel delivery system has been failing in the same manner that I have seen many other Cadillac owners have gotten repaired through a recall already in place. Every single time I put gas in the tank the car refuses to turn on with the first attempt. The only way to get the car to turn on is after multiple attempts and finally enough fuel gets delivered to the system. Similarly, the car will…
The car spark plugs keep going out and the car is make a clicking noise it is silender 1 and 3.
Had engine trouble with your 2006 Cadillac STS?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2006 Cadillac STS?
It's a meaningful issue. 18 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $3,100.
At what mileage does the engine typically fail?
Across the 15 complaints that reported odometer mileage, most engine failures cluster between 57,233 and 96,000 miles, with the median around 76,663. A quarter of owners report trouble before 57,233; a quarter make it past 96,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2006/Cadillac/STS.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.