2006 Cadillac STS Problems

What owners report

Owners of the 2006 Cadillac STS most often report a persistent air bag warning — usually traced to the passenger presence sensor or module — and say the repair is expensive and not covered. Many complaints note that a similar system was addressed on other Cadillac models of the same years but not on the STS. Stall and intermittent no-start reports are the next most common theme, and some owners tie fuel delivery symptoms to an existing fuel pump recall that their vehicle was not included in.

1. 1
   Air bags

   Air bag warning light / passenger presence sensor failure

   • 49 complaints (35%)
   • median 82,000 mi at 9.1 yrs old (42 state mileage)
   • 9 mention a crash, fire or injury
   • owner-quoted repair $900 (median of 9 quotes)
   • filed 2005–2020

   Owners describe a "Service Air Bag" message or an air bag indicator that stays lit, sometimes with the passenger air bag status showing off even when the seat is occupied. Several say the dealer diagnosed a faulty passenger presence module or sensor and quoted repairs in the hundreds to about a thousand dollars with programming. Complaints frequently note that a similar condition led to a recall on other Cadillac models of these years, while the STS was not included, and that the dealer and manufacturer declined assistance. Reported from very low mileage up to about 150,000 miles, often appearing after start-up or during a drive without warning.

   What to check: With the engine on, confirm the air bag warning light goes out and that the passenger air bag status reads correctly with someone seated. Ask for any repair invoice for the passenger presence module.

   2 excerpts from owner complaints in NHTSA records

   “I'm currently transporting elder clients without any airbags in my vehicle for the past six weeks. There was a recall on the 2006 cts, but not the STS for the same issue. There are numerous complaints online about the same issue on the 2006 STS. My dealer refuses to honor my request to repair the passenger seat sensor (which controls the airbags) under recall. Thank-you!”

   NHTSA complaint #10716199, filed 2015-05, 82,000 miles

   “Started receiving a constant, service air bag warning message after 125,000 miles. The dealer told me the passenger presence module needed replaced. It will cost $1,000 for the part, labor, and programming. Now I read on this forum that the same issue was found on the cts model and it was recalled by the manufacturer, but not the STS. It's difficult to justify putting that much money in an older vehicle.”

   NHTSA complaint #11025314, filed 2017-09, 125,000 miles
2. 2
   Engine

   Engine stalls or shuts off while driving

   • 23 complaints (17%)
   • median 69,000 mi at 8.5 yrs old (21 state mileage)
   • 6 mention a crash, fire or injury
   • filed 2005–2020

   Owners report the engine cutting out without warning at cruising or lower speeds, sometimes repeatedly within a short distance, with the accessory or stability light coming on. Some say the car would restart only after being shifted to neutral or after several attempts, and dealers sometimes replaced the ignition switch or auto-start component. Other complaints describe the dealer being unable to reproduce the problem. Reported from a few thousand to about 150,000 miles, with many accounts between roughly 60,000 and 90,000 miles.

   Recall 06V007000

   What to check: Ask whether the ignition switch or start system has been replaced, and take a test drive that includes steady highway speed plus stop-and-go to see whether the engine cuts out.

   2 excerpts from owner complaints in NHTSA records

   “Car shuts off while driving happen 4 times it starts up go about half a mile shuts off again after 4 times it was ok until about a month later it happen again.”

   NHTSA complaint #10508324, filed 2013-04, 65,000 miles

   “The contact owns a 2006 Cadillac STS. While driving 30 MPH, the vehicle anti-theft system and the brakes seized without warning causing the vehicle to stall. The failure recurred several times. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The VIN was not available. The failure mileage was 119,000.”

   NHTSA complaint #10684304, filed 2015-02, 119,000 miles
3. 3
   Fuel system

   Fuel delivery problems and hard starting

   • 12 complaints (9%)
   • median 91,500 mi at 10.0 yrs old (10 state mileage)
   • 1 mention a crash, fire or injury
   • filed 2013–2021

   Complaints describe extended cranking, the engine refusing to start on the first attempt, and hesitation or a drop in power at highway speed that owners suspect is a lack of fuel delivery. Some report fuel smells or visible fuel leaking at the tank, and a few connect these symptoms to a fuel pump recall that their vehicle was not covered by. Diagnostics mentioned include fuel pump wiring, a check valve, and repeated dealer attempts without a lasting fix. Mostly reported between about 45,000 and 140,000 miles.

   Recall 14V542000Recall 06V0200001 related service bulletin

   What to check: Check whether the vehicle's VIN is included in the fuel pump recalls, and ask about any history of hard starting or fuel smell; inspect under the rear of the car for fuel residue.

   2 excerpts from owner complaints in NHTSA records

   “My car has been diagnosed as having 'extended crank'. My local chevy dealer made approximately fifteen attempts at fixing it to no avail. I'm told it's the check valve, but I have not had that done because all attempts by the dealer didn't work; e.g., new computer (and removed), battery (and removed), fuel pump, etc. Very frustrating and I feel it's a matter of health and safety because the car almost never starts on the first attempt, and sounds like it's a dead battery.”

   NHTSA complaint #11318139, filed 2020-03, 100,000 miles

   “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 hesitate or feel like no gas is being delivered to the engine while driving on the highway. …”

   NHTSA complaint #10661288, filed 2014-11, 45,000 miles
4. 4
   Electronic stability control

   Hesitation or stall on turns with stability message

   • 6 complaints (4%)
   • median 61,696 mi at 7.4 yrs old (6 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2010–2017

   Owners describe the car briefly refusing to accelerate, or stalling, typically while making a right turn from a stop, with the traction or stability message appearing on the dash. The condition is intermittent and clears after a few seconds, but owners say it leaves them unable to keep up with traffic. Dealers reportedly suggested fuel treatment or could not duplicate it, and in some cases diagnosed the stability system. Reported from very low mileage to about 140,000 miles.

   Recall 06V007000

   What to check: During a test drive, make several slow right turns from a stop and watch for a traction/stability message or a momentary loss of acceleration.

   2 excerpts from owner complaints in NHTSA records

   “After purchasing a used 2006 STS awd from Cadillac nj in december 2009, wife noticed while making right hand turns on smooth pavement, car seems to stall temporarily not allowing me to accelerate for a few seconds and message traction active is displayed. January 18, 2010,I brought the car back to dealership to complain. They said prob bad gas in lines. Put new gas in and gas treatment for water in tank. Did that, didn't help. February 1, 2010 I returned to dealership to complain it was still doing it on occasion. …”

   NHTSA complaint #10459155, filed 2012-05, 53,393 miles

   “When making right hand turns, the car stalls temporarily not allowing me to accelerate or acclimate to oncoming traffic. While this is happening, the traction active symbol is displayed on the dashboard. Within a few seconds it seems to all work again, however it seems to be a safety issue as other cars are either assuming I will be at their speed, or assume I am allowing them to go when in fact I am stuck. I have 3 children in the car and I am becoming scared that this may cause an accident and is a major safety concern.”

   NHTSA complaint #11001777, filed 2017-06, 84,000 miles
5. 5
   Engine

   Timing chain wear and engine noise

   Mentioned in 4 of 60 sampled complaints

   Some owners describe an abnormal noise from the engine compartment or a check engine light, with the dealer diagnosing a stretched or worn timing chain that needed replacement. Others mention rough running, misfire-like symptoms, and loss of power that led to the same diagnosis. Complaints also note the repair was done at owner expense. Reported between roughly 55,000 and 85,000 miles.

   3 related service bulletins

   What to check: Listen for rattling or whining from the front of the engine at cold start, and ask for records of timing chain, oil consumption, or misfire-related repairs. Check the oil level and condition.

   2 excerpts from owner complaints in NHTSA records

   “On thursday 18 may 2017, while driving north on interstate 405 in heavy traffic at normal speeds, the engine began to miss out; and the brakes lost power assist. The problems persisted and worsened, so I exited the freeway to surface streets and began the trip back south on interstate 405 to take the vehicle to the dealer for diagnosis and repair. When stopped on surface streets (and on the freeway), it was necessary to shift to neutral and add fuel to the engine to keep it running. …”

   NHTSA complaint #11002667, filed 2017-07, 83,000 miles

   “The contact owns a 2006 Cadillac STS. While driving approximately 35 MPH, the engine warning indicator remained illuminated. The vehicle was taken to an authorized dealer for diagnostic testing. The mechanic stated that the timing chain stretched and needed to be replaced. The vehicle was repaired. The manufacturer was notified. The approximate failure mileage was 53,820.”

   NHTSA complaint #10622119, filed 2014-08, 53,820 miles

Buying note. Check the air bag and stability warning lights carefully and ask for repair records for the passenger presence module, ignition switch, and fuel pump. Confirm whether the vehicle's VIN falls under the open fuel system recalls before purchase.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.