Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2003 Cadillac Deville owners, lightly cleaned up (personal details are redacted by NHTSA).
I tried to explain to the dealership that unaware of the recall my cars breaks had failed and crashed my vehicle. They said the only thing that was affected was the key. I had told her that the result of my crash was from my breaks not working due to the recall. She told me no that that wasnt affected. I just want my car to be safe on the road as i have kids, and family that ride with me regularly.
After taking off from a stop sign, I drove up over about 1 1/2 inch vertical rise in the pavement (small bump). The engine and electrical systems shut down. I lost power stirring and power brakes. I got stopped and restarted the engine. This occurred about 3 days after I had taken my car to the GM dealer for repairs covered by GM recall 14299, "unintended ignition key rotation". My key did not rotate. Yesterday April 2, 2015 when driving 45 MPH on a state highway, the engine stopped again without hitting any bumps. I was able to coast, put the car in neutral, and restart the engine, before the car behind me could hit me. There was no shoulder to pull off.again there was no key rotation. I called my GM dealer after the first occurrence and was told I would have to pay for a new ignition switch or what ever was causing the problem. …
Tl* the contact owns a 2003 Cadillac Deville. While driving approximately 30 MPH, the vehicle stalled without warning. As a result, the contact crashed the vehicle into a parked vehicle. The air bags failed to deploy. The contact sustained neck and jaw injuries and the other two passengers sustained neck and back injuries that required medical attention. The vehicle was towed to the contact's residence and was not diagnosed or repaired. The contact received a recall notification for NHTSA campaign number: 14V355000 (electrical system); however, the parts needed for the repair were unavailable. The manufacturer was not notified of the failure. The approximate failure mileage was 120,000.
Tl* the contact owns a 2003 Cadillac Deville. The contact stated that the service engine light was illuminated. The vehicle was taken to the arrowhead Cadillac (8310 w bell rd, glendale, az 85308 [phone]) where it was informed that the torque converter needed to be replaced. The vehicle was not repaired. The manufacturer was contacted however no further assistance was provided. The failure mileage was 79,000. The VIN was not available. VIN is invalid.
My engine leaks oil from the seals. It was always dealer maintained for regular maintenance with low mileage. It started 3 years ago. I noticed you recalled other vehicles for this problem. My engine is a v8. Regular oil changes etc. It continues to leak. Dealer wants $2,500 to fix seals. The way I drive it with low millage of 60,000 miles it should not have leaked. Just read about recall of other GM cars on 27 oct. 2015.
2003 Cadillac Deville with approx. 65,900 miles on 07/11/07. The "service engine soon" warning light appeared on vehicle control panel & took vehicle to dealership same date 07/11/07. Dealer performed oil change & informed that entire transmission is about to fail & quoted $4,027.00 for repairs. Dealer refused to honor warranty past 50,000 miles & informed entire cost was the responsibility of the customer. GM was contacted & refused to provide any financial or repair assistance for defect and repeatedly delayed any decision until approximately 08/02/07 (after repeated attempts by customer to contact/resolve problem), other than a $1,000.00 customer loyalty certificate to buy a new car on approx 8/02/07. GM representative called & recorded phone conversation with customer without customer advance knowledge or consent on 8/01/07 & 8/02/07. …
I was driving at approximately 60 mhp on i77 north - without notice of any kind it became very difficult to steer my vehicle and I lost control as well as all power & acceleration. All of this happened so fast but I looked down and noticed several dash board/warning lights on. These lights normally only go on for a second or so when starting the car. Having no power or acceleration I was able to navigate my car to the side of the road with out an accident but immediately noticed that my ignition was already turned off. The ignition key was not all the off - just in the position as if I was parked and wanted to listen to the radio. Once pulled over I placed the car in "park" turned the key all the way off and restarted the car. It started right up. However, now both my "service engine soon light" and "air bag" light stays illuminated at all times. …
2003 Cadillac Deville. Consumer writes in regards to several mechanical defect issues. Consumer sent additional correspondence. The consumer stated the water pump and radiator leaked resulting in a coolant leak, and the engine overheating. An independent mechanic determined the metal brackets holding the left side tank had rusted and caused a crack in the left radiator tank. The engine developed an oil leak from the lower crankcase of the engine block. The oil leak caused a defective design in the lower crank shaft. The mechanic informed the consumer the engine needed to be removed to properly repair the oil leak. Also, the tire pressure light illuminated. The consumer stated that a diagnostic from OnStar of the vehicle displayed a malfunctioned airbag. The consumer requested a formal investigation into these issues. …
I have been having problems with this vehicle from day one if checked cadlliac records, it will indicate as a brakes problem. 1 had 4 brake jobs done on the vehicle to find out later that it was not the brake, now they said it was the wheel beariing, which sound the same as when they told me brakes. The vehicle failed inspection in delaware because of the emmissions system ,at that time the vehicle was covered by warranty. I assume Cadillac fixed the problem to find out later they never replaced the catalytic converter. I have had many conversations with Cadillac with no help, they gave me a voucher toward a new vehicle which was not going to help me with my situation . Because no one wants to buy a vehicle that has problems from the door,please someone help me to get my problem resolved, I'm tryng to get my vehicle fix , so I can upgrade,
Tl* the contact owns a 2003 Cadillac Deville. The contact stated that the ignition switch failed to start the vehicle and the key was hard to remove from the ignition. In addition, the air bag warning indicator illuminated upon attempting to start the vehicle, which was a safety concern. The vehicle was towed to the contact's residence where an independent mechanic diagnosed that a security module failed and there was a disconnection of the electrical system. The vehicle was then taken to vinings enterprises inc. (904 n tennessee st, cartersville, ga 30120, [phone]), but the failure could not be diagnosed. The vehicle was not repaired. The manufacturer was not notified. The failure mileage was unavailable.
Engine complaints in other Deville years
Frequently asked questions
How common are engine problems on the 2003 Cadillac Deville?
NHTSA has 26 complaints about the engine & cooling of the 2003 Cadillac Deville, 18% of the model year's 145 complaints. The component named most often is engine (4 mentions).
Is there a recall for 2003 Cadillac Deville engine problems?
No. NHTSA lists no engine & cooling recall for the 2003 Cadillac Deville, though it has 4 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2003 Cadillac Deville engine problems start?
Half of the complaints with a recorded mileage happened before about 64,000 miles, and 26% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 0 fires and 3 injuries to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.