2020 Cadillac CT4 Problems: 2 Issues Every Owner Should Know
2020 model year · 0+ owner reports · Updated April 2026
According to Au7o's analysis of 0+ owner reports, the 2020 Cadillac CT4 has 2 documented known issues. No issues are rated critical, indicating generally reliable ownership. Across all issues, repair costs range from $0 to $1,200. DIY maintenance guides at au7o.io.
All 2 Known Issues
On the 2020-2025 Cadillac CT4, the CT4 base model uses the 2.0T LSY engine which shares the valve cover/PCV failure and turbo coolant line concerns found in the XT4. The PCV system integrated into the valve cover can fail between 40,000-80,000 miles, causing oil consumption, vacuum leaks, and rough idle. Turbo coolant line connections can develop slow leaks. The CT4-V uses a 2.7T engine (L3B) with different issues. The CT4-V Blackwing uses the 3.6L Twin-Turbo (LF4) which is bespoke and generally reliable.
Common Symptoms
- Check engine light with misfire or lean codes
- Excessive oil consumption
- Rough idle
- Coolant level dropping slowly
- Turbo-related noises or performance changes
How to Fix
Replace valve cover assembly for PCV failure (GM updated design available). Inspect and replace turbo coolant lines if leaking. 5,000-mile oil change intervals with full synthetic are important for turbo longevity.
What Owners Are Using
Parts and tips from 0+ owners who fixed this issue
- TipSame LSY 2.0T turbo as XT4. GM Turbocharger Coolant Feed Pipe (12691901) plus gasket (55504552) are the primary failure points. Inspect at every oil change for coolant weeping around turbo area. Replace preventively at 60,000 miles
- TipGM PCV Valve 55514392 is the same LSY-specific part across all applications (CT4, XT4, Equinox, Malibu). PCV failure symptoms: excessive oil consumption, check engine light, boost pressure codes. Relatively inexpensive part ($30-50) but labor can be $200+ at dealer
- Tip5,000-mile oil change intervals with dexos1 Gen 3 0W-20 are critical for LSY turbo longevity. Monthly coolant level checks catch turbo coolant line leaks early. The CT4-V Blackwing uses a different engine (LF4 3.6TT) and is NOT affected by these LSY-specific issues
- UpgradeTurbo gasket kit prevents boost leaks and oil seepage at the turbo flanges (Dorman Turbocharger Gasket Kit)
- UpgradeBoost gauge helps monitor turbo performance and catch problems early (AutoMeter Mechanical Boost Gauge)
On the 2020-2022 Cadillac CT4, the 2020-2022 CT4 infotainment system (Cadillac User Experience) suffers from slow response times, screen freezing, and significant glitches. The touchscreen can become unresponsive, the radio may produce no sound, and the turn signal audio indicator can fail. Cadillac has released software updates to address some issues, but problems persist for some owners.
Common Symptoms
- Touchscreen slow to respond or frozen
- No sound from radio or speakers
- Turn signal click sound not working
- Screen goes black on startup
- Bluetooth connectivity drops repeatedly
How to Fix
What Owners Are Using
Parts and tips from 0+ owners who fixed this issue
- UpgradeProfessional OBD-II diagnostic scanner for reading infotainment and body module codes (BlueDriver Bluetooth Pro OBD2 Scan Tool)