General Motors has not earned a reputation for producing the most reliable cars of the modern era. Many reports of electrical failures, engine problems, transmission failures and even turbochargers say this before 60,000 miles on engines like the 1.4L Ecotec. That’s not to say GM hasn’t produced some gems. Just about anything with the 3800 V6, pre-active fuel management LS engines, and even the 3.6L V6, once the timing chain issue is worked out, can be great, economical vehicles to own for the long haul . Ultimately, every brand has its ups and downs, but today we’re going to explore the most common problems with General Motors’ most premium brand: Cadillac.
1. Electric lift failure
According to RepairPal, the most common problem is a failed window regulator. RepairPal has received over 700 reports of this error. Owners say the windows won’t roll down or, even worse, won’t roll back up, bad news if you don’t have a garage or garage. Some even claimed to have replaced several regulators during a year or two of ownership. In fact, many owners reporting their experience on RepairPal describe replacing multiple regulators and even replacing them soon after.
The culprit of such an incredible failure rate is a small plastic wheel. Unfortunately for Cadillac owners, the window regulator is only sold as a complete unit and cannot be repaired independently. That means your repair bill will be between $400 and $500 each time. The car in question is the Cadillac DeVille. Most of the reports seem to be for eighth generation DeVilles sold between 2000 and 2005, but RepairPal says the affected model years are 1990-2005.
2. Mixture gate actuator failure
The second most common Cadillac issue on RepairPal is cabin heat and air conditioning delivery. These 600+ reported problems are new for a 1990-2005 Cadillac DeVille. Airflow control and temperature are regulated by a part called the mixing door actuator. According to owners information, their combination door actuators act up or fail completely regardless of mileage.
The mixing door actuator works with your temperature and airflow controls; depending on the vehicle, you may have more than one. The mixing door controls where the air comes out and what temperature the air is, and the actuator moves that door. For example, if you set the temperature to 60 degrees Fahrenheit (or to the blue side of the temperature dial in cars without automatic climate control), the mixing door will allow a “mix” of hot and cool air to pass into the cabin to achieve the desired temperature.
If the actuator fails, the door will not be able to move along with the HVAC controls. As a result, many symptoms report that the airflow is stuck coming out of the defrost vents or only coming out of the floor vents. Other owners describe hot air coming out one side and cold air coming out the other, regardless of how the controls are set. RepairPal reports that the average cost to repair a combination door actuator on a Cadillac DeVille is between $882 and $1002.
3. The Northstar engine leaks like crazy
The third most common Cadillac problem has over 500 reports on RepairPal. Here’s a fact that won’t surprise anyone: It’s another Cadillac DeVille that’s causing all the trouble! RepairPal notes that the affected years are 1990-2005, but this oil leak issue is really only a concern for DeVilles equipped with the 4.6L Northstar V8. The Northstar was introduced for the seventh-generation DeVille that started in 1994, so it’s a safe bet that an earlier-generation DeVille won’t have this exact problem.
The Northstar can leak from many, many, many places. As many owners have pointed out, the most expensive leak is the lower sump. This may require an engine out service to repair and can cost anywhere from $2,000 to $2,500. According to RB Auto Service, which specializes in Northstar engines, there are pressure passages in the lower crankcase, so these leaks can be twisted.
Frankly, unless you love your Northstar Caddy, the best financial decision is to avoid them like the plague. That said, if you have one and want to fix these leaks, the repair process is well documented and many shops are familiar with the widespread nature of this problem. It could just be expensive.
4. Early chip keys can spell trouble for DeVille owners
The 1990s and early 2000s saw the introduction of chip keys. These types of wrenches aren’t just about turning the ignition barrel. The key has a chip that must be present and working to signal the anti-theft system for the car to start. If you lose a key, a copy will not work unless programmed.
If it’s not a key issue, the small wires in the ignition lock cylinder also tend to break, causing a no-start condition. Some reports claim that these cables can break prematurely if you have other keys on your key fob, which most people do. The added weight seems to advance the deterioration of the already weak connection. The average mileage for this problem is usually around 120,000, and RepairPal says the average cost to replace the ignition barrel, not including reprogramming and cutting keys, is around $250.
