CADILLAC STS · model year

1999 CADILLAC STS

16 NHTSA complaints for this specific cohort.

NHTSA overall rating

Not crash-tested

New Car Assessment Program

The 1999CADILLACSTS carries 16 consumer safety complaints in NHTSA's Office of Defects Investigation database for this specific model-year cohort. Within that volume, owners reported 0 crashes, 1 fire, 0 injuries, and 0 fatalities. No NCAP 5-star crash-test rating is available for this model year in the federal database.

Component-level analysis is where model-year complaints become actionable: the top complaint category for the 1999 STS is electrical system with 6 filings, followed by engine and engine cooling:engine (3) and engine and engine cooling (3). Concentration in one or two component groups is the classic signature of a systemic defect; a flat distribution usually reflects normal aging, warranty complaints, or isolated build-plant variability.

NHTSA currently has 10 investigation files overlapping the 1999 STS, and 1 remain open. Owners comparing this cohort against neighboring years should pair the counters above with the complaint-by-year trend on the parent model page — a spike in a single year often tracks to a platform refresh, a new transmission supplier, or an updated ECU calibration. Use the related-complaint feed below to read raw owner narratives before deciding whether any pattern here affects your specific use case.

16
Complaints
0
Crashes
1
Fires
0
Injuries
0
Deaths

Total Complaints

16 filings

Crashes Reported

0 reports

Source

NHTSA ODI

Federal complaints database

Complaints vs. fleet median (215)

At or below the fleet median complaint volume.

Complaints by Component

ComponentCount
ELECTRICAL SYSTEM6
ENGINE AND ENGINE COOLING:ENGINE3
ENGINE AND ENGINE COOLING3
ENGINE2
STEERING1
SUSPENSION:FRONT1

Recent Complaints

20140912ENGINE AND ENGINE COOLING

OUR STS STALLED SEVERAL TIMES, BUT THE SCARIEST WAS ON THE HIGHWAY GOING 65 MPH. THE CAR TOTALLY SHUT OFF, LEAVING THE CAR WITHOUT ANY POWER. WE WERE ABLE TO GUIDE THE CAR TO THE SIDE OF THE HIGHWAY AND THANK GOODNESS IT STARTED AGAIN. ON SEVERAL OTHER OCCASIONS, THE CAR WOULD SHUT OFF AND SOMETIMES WOULDN'T EVEN START UP RIGHT AWAY. THIS WAS VERY FRUSTRATING AND THE UNKNOWING, MADE DRIVING THIS CAR VERY UNPREDICTABLE. EVERY TIME WE BROUGHT THE CAR TO BE CHECKED THEY COULD NOT FIND "ANYTHING". FINALLY, AN INDEPENDENT MECHANIC SUGGESTED PUTTING IN A NEW STARTER AND THIS SOLVED THE PROBLEM. THANK GOODNESS. THE SEVILLE STS IS NOW RUNNING, BUT THE A/C HAS GONE OUT. THE CAR IS TOO OLD TO EVEN FIX AT THIS POINT. *TR

Mileage: 98,587

20121023FireENGINE

TL* THE CONTACT OWNS A 1999 CADILLAC STS. THE CONTACT STATED THAT WHILE DRIVING AN UNKNOWN SPEED, THE ENGINE RPMS INCREASED AS SMOKE WAS RELEASED FROM UNDER THE HOOD. THE VEHICLE WAS TOWED TO THE MECHANIC WHO PERFORMED A DIAGNOSTIC. THE FAILURE WAS LOCATED AT THE ENGINE MOTOR BOLTS, WHICH HAD BECOME DISCONNECTED DUE TO DEFECTIVE METAL. THE BOLT COIL AND THREAD WAS REPLACED HOWEVER, THE FAILURE RECURRED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE VEHICLE WAS NOT FURTHER REPAIRED. THE FAILURE MILEAGE WAS 80,000 AND CURRENT MILEAGE WAS 100,000. UPDATED 12/12/12*LJ UPDATED 12/13/2012 *JS

Mileage: 80,000

20120813ENGINE

TL* THE CONTACT OWNS A 1999 CADILLAC STS. THE CONTACT STATED THAT THE HEAD BOLTS WERE NOT THE CORRECT SIZE FOR THE ENGINE AND AS A RESULT, THEY STRIPPED, CAUSING THE ENGINE HEAD TO DETACH FROM THE VEHICLE. THE VEHICLE WAS TAKEN TO THE DEALER WHO DIAGNOSED THAT THE ENGINE NEEDED TO BE REMANUFACTURED. THE VEHICLE WAS REPAIRED HOWEVER, THE FAILURE RECURRED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE VEHICLE WAS NOT FURTHER REPAIRED. THE VIN WAS NOT AVAILABLE. THE FAILURE MILEAGE WAS 128,000 AND THE CURRENT MILEAGE WAS UNKNOWN.

Mileage: 128,000

20120522ELECTRICAL SYSTEM

HAVING PROBLEMS WITH CAR KEEP CHARGE, SOMETHING IS PULLING OR DRAINING THE BATTERY, BATTERY BEEN REPLACED 3 TIMES AND STILL THE SAME PROBLEMS SOMETIMES YOU GET IN THE CAR AND IT START OTHER TIME IT WON'T. I COMMUTE 1 HOUR AWAY FROM HOME AND THIS IS A PROBLEM. I HAVE TO KEEP CALLING ALLSTATE TO GIVE ME A JUMP THIS IS RIDICULOUS. SOMETHING MUST BE DONE. *TT

20100216ELECTRICAL SYSTEM

GM'S RECALL NUMBER IS 99013. *TR

Mileage: 106,244

20100216ENGINE AND ENGINE COOLING

1999 CADILLAC SEVILLESTS. 100,600 MILES ON ODOMETER. WHILE DRIVING AT SLOW SPEED (IN TOWN) , ENGINE WILL STOP ENTIRELY,.- I LOSE MY POWER STEERING, BRAKES AND EVERYTHING ELSE . WHEN I GET STOPPED, ENGINE WILL START IMMEDIATELY. I'E HAD THE BATTERY CHECKED, AND AM TOLD ALL THE CONNECTIONS WERE "FINE". A GM DEALER RECENTLY TUNED THE ENGINE , AND SUGGESTED THAT HE REPLACE THE WIRING" HE DID SO. HE DID THIS @ TWO MONTHS BEFORE THE TROUBLE STARTED. THE DEALER IS OUT OF BUSINESS. I AM AFRAID TO DRIVE THE CAR -- SUPPOSE THIS HAD OCCURRED WHILE DRIVING 65-70 MPH ON THE INTERSTATE. ??? PLEASE ADVISE ME!!! RIVING, ENGINE WILL STOP ENTIRELY - I LOSE MY POWER STEERING, BRAKES, AND EVERYTHING ELSE. WHEN I GET STOPPED, THE ENGINE WILL START IMMEDIATELY. HAVE CHECKED BATTERY CONNECTION AND IT CHECKS "FINE". *TR

Mileage: 100,600

20091124STEERING

RACK /PINION BROKE WHILE DRIVING DOWN ROAD. *TR

Mileage: 174,000

20091124SUSPENSION:FRONT

RACK /PINION BROKE WHILE DRIVING DOWN ROAD. *TR

Mileage: 174,000

20061221ENGINE AND ENGINE COOLING

I BOUGHT A 1999 CADILLAC STS FROM A DEALER IN MORGANTOWN, WV. IT WAS A COUPLE OF YEARS OLD. NOW, IT HAS ABOUT 124,000 MILES ON IT. AFTER A FEW TRIPS TO THE DEALERS SERVICE DEPARTMENT RECENTLY, I WAS TOLD THE REASON MY CAR WAS RUNNING ROUGHLY WAS BECAUSE THERE WAS A LEAKING HEAD GASKET. UNFORTUNATELY, THE DEALER SAID, THEY WON'T TRY TO REPAIR IT BECAUSE THEIR EXPERIENCE WITH THE CADILLAC NORTHSTAR ENGINE IS THAT IF THEY TRY TO REMOVE IT, IT STRIPS SOME SORT OF BOLT OR THREAD, RUINING THE ENGINE. I HAVE BEEN IN TOUCH WITH CADILLAC BY TELEPHONE AND BY E-MAIL SEVERAL TIMES TO ASK IF IT IS TRUE THAT THEY HAVE DESIGNED AND SOLD A CAR THAT CAN'T BE REPAIRED. THEY WOULDN'T ANSWER ME DIRECTLY; INSTEAD, THEY SAID MY CAR IS OUT OF WARRANTY AND NO LONGER THEIR RESPONSIBILITY. FINALLY, SOMEONE CONCEDED THAT IT IS TRUE. I AM SHOCKED THAT A COMPANY LIKE CADILLAC CAN DESIGN AND DELIVER A CAR, KNOWING THAT CERTAIN MAJOR PROBLEMS CAN'T BE REPAIRED. *NM

20060919ELECTRICAL SYSTEM

WHILE DRIVING AT VARIOUS SPEEDS AS WELL AS AT IDLE, VEHICLE SHUTS OFF. NO POWER STEERING, BRAKES, ELECTRIC, ETC. VEHICLE IS THEN DIFFICULT TO START, MUST WAIT SEVERAL MINUTES BEFORE SUCCESS. VERY DANGEROUS- HAS HAPPENED AT HIGHWAY SPEEDS SEVERAL TIMES ON BUSY INTERSTATE. DATE GIVEN IS JUST ONE OF AT LEAST 8 FAILURES. *NM

20060510ENGINE AND ENGINE COOLING:ENGINE

DT*: THE CONTACT STATED WHILE DRIVING AT VARIOUS SPEEDS THE VEHICLE STALLS WITHOUT WARNING RESULTING IN LOSS OF POWER. AFTERWARDS, THE VEHICLE RESTARTS IN LESS THAN A MINUTE. THE STALLING OCCURS INTERMITTENTLY AND HAS GRADUALLY BECOME WORSE. THE VEHICLE WAS TAKEN TO AN INDEPENDENT REPAIR SHOP FOR INSPECTION WHO WAS UNABLE TO DETERMINE THE CAUSE OF THE PROBLEM.

Mileage: 91,000

20060510ELECTRICAL SYSTEM

DT*: THE CONTACT STATED WHILE DRIVING AT VARIOUS SPEEDS THE VEHICLE STALLS WITHOUT WARNING RESULTING IN LOSS OF POWER. AFTERWARDS, THE VEHICLE RESTARTS IN LESS THAN A MINUTE. THE STALLING OCCURS INTERMITTENTLY AND HAS GRADUALLY BECOME WORSE. THE VEHICLE WAS TAKEN TO AN INDEPENDENT REPAIR SHOP FOR INSPECTION WHO WAS UNABLE TO DETERMINE THE CAUSE OF THE PROBLEM.

Mileage: 91,000

20060327ELECTRICAL SYSTEM

VEHICLE SHUTS DOWN AT CRUISING SPEEDS, LOW SPEEDS, AND IDLING. ALL SYSTEMS SHUT DOWN WITHOUT WARNING. VEHICLE MAY OR MAY NOT START BACK UP IMMEDIATELY. I HAVE SEEN SEVERAL OTHER COMPLAINTS ON SAME ISSUE BOTH ON NHTSA AND OTHER CHAT BOARDS. THIS CAUSES A HAZARDOUS DRIVING CONDITION FOR MYSELF AND OTHER DRIVERS. CAN BE ESPECIALLY DANGEROUS ON HILLY AND CURVED ROADS BECAUSE ALL POWERED STEERING AND BRAKING SHUTS DOWN AS WELL. *JB

20060327ENGINE AND ENGINE COOLING:ENGINE

VEHICLE SHUTS DOWN AT CRUISING SPEEDS, LOW SPEEDS, AND IDLING. ALL SYSTEMS SHUT DOWN WITHOUT WARNING. VEHICLE MAY OR MAY NOT START BACK UP IMMEDIATELY. I HAVE SEEN SEVERAL OTHER COMPLAINTS ON SAME ISSUE BOTH ON NHTSA AND OTHER CHAT BOARDS. THIS CAUSES A HAZARDOUS DRIVING CONDITION FOR MYSELF AND OTHER DRIVERS. CAN BE ESPECIALLY DANGEROUS ON HILLY AND CURVED ROADS BECAUSE ALL POWERED STEERING AND BRAKING SHUTS DOWN AS WELL. *JB

20051011ELECTRICAL SYSTEM

ON 11/27/00 CAR LEASED FROM CHEVY DEALER AND ONSTAR PUT ON BY CADILLAC DEALER. ON 01/08/01 CAR DEAD IN DRIVE,CADILLAC DEALER INSTALLED NEW BATTERY. ON 10/01/01 CAR QUIT WHILE DRIVING, CADILLAC DEALER INSTALLED NEW GENERATOR. ON 7/18/02 CAR DEAD IN DRIVE,CHEVY DEALER REPLACED GENERATOR. ON 9/13/04 CAR DEAD IN DRIVE ,CHEVY DEALER FOUND NOTHING. ON 11/18/04 CAR DEAD IN DOCTOR'S LOT,CHEVY DEALER FOUND NOTHING AND SENT IT TO CADILLAC DEALER WHO ALSO FOUND NOTHING. TWO DAYS LATER CAR DEAD IN STORE LOT. SENT BACK TO CADILLAC DEALER WHO INSTALLED GENERATOR AND BATTERY. ON 8/31/05 CAR STALLED AFTER BEING PICKED UP FROM CHEVY DEALER, RETURNED TO CHEVY DEALER WHO FOUND NOTHING. SENT TO CADILLAC DEALER WHO REPLACED SOME COMPUTERS. CHEVY DEALER PICKED CAR UP AND DRIVE 9 MILES BEFORE CAR QUIT. RETURNED TO CADILLAC DEALER WHO REPLACED IGNITION SWITCH. RETURNED TO ME. FIVE(5) DAYS LATER CAR DEAD IN DRIVE AND RETURNED TO CADILLAC DEALER. CADILLAC DEALER DISCONNECTED ONSTAR AND SAID TRY IT.

Mileage: 35,124

20050525ENGINE AND ENGINE COOLING:ENGINE

1999 CADILLAC STS EXPERIENCING PROBLEMS WITH WATER SOUNDS BEHIND THE DASHBOARD AS WELL AS THE ENGINE OVERHEATING.*MR THE DEALER REPLACED THE WATER PUMP BUT THAT DID NOT RESOLVE THE PROBLEM. WHILE DRIVING THE ENGINE LIGHT ILLUMINATED AND A WARNING BELL SOUNDED. THE VEHICLE WAS TAKEN TO THE DEALER WHO INDICATED THAT THE ENGINE HAD TO BE REPLACED. TWO MONTHS AFTER THE ENGINE WAS REPLACED THE ENGINE IDLE AND OVERHEATING LIGHT ILLUMINATED. THE ENGINE WAS REPLACED AGAIN. THE MANUFACTURER WAS CONTACTED AND REFUSED TO PROVIDE ANY ASSISTANCE. *NM

Mileage: 67,000

Compare 1999CADILLACSTS to Similar Vehicles

NHTSA Investigations 1 Open

View all investigations

Frequently Asked Questions

How many complaints does the 1999 CADILLAC STS have?
The 1999 CADILLAC STS has 16 NHTSA complaints, 0 crashes, 1 fires, 0 injuries, and 0 deaths reported.
What are the most common problems with the 1999 CADILLAC STS?
The most-complained component for the 1999 CADILLAC STS is ELECTRICAL SYSTEM with 6 complaints. Other frequently reported areas include ENGINE AND ENGINE COOLING:ENGINE and ENGINE AND ENGINE COOLING.
Is the 1999 CADILLAC STS safe to buy?
Review the complaint history, crash and fire reports, safety ratings, and recall status on this page to make an informed decision. No NHTSA crash test rating is available for this model year. Compare with other model years using the links above.
Where does this data come from?
All complaint, recall, and safety rating data is sourced from the National Highway Traffic Safety Administration (NHTSA). Complaints are filed by vehicle owners through NHTSA's Office of Defects Investigation.

Vehicle Safety Guides

Data as of 2025. Sources: NHTSA Office of Defects Investigation (ODI) complaints database, NHTSA recall campaign API, NHTSA NCAP crash-test ratings, and NHTSA FARS for fatality cross-reference.