Buyer's Guide
What to know before purchasing a 991
Overview
The Porsche 991 (2012-2019) represents the modern evolution of the 911, with increased dimensions, improved technology, and the introduction of turbocharged engines across the range in 991.2. The 991 offers exceptional performance (350-700 hp depending on variant), modern amenities, and excellent reliability. While the naturally aspirated 991.1 engines are praised by purists, the turbocharged 991.2 offers more everyday power. GT3, GT3 RS, and GT2 RS variants continue to set benchmarks for track performance.
Quick Facts
Production
2012-2019
Total Produced
~217,000 worldwide
Price Range
$60,000 - $400,000+
Best Years
2017-2019 (991.2 refined, proven reliability)
Model Variants
Carrera / Carrera S (991.1)
2012-2016
Naturally aspirated with 3.4L (350 hp) or 3.8L (400 hp). Purist choice with high-revving character.
Desirability:
High
Carrera / Carrera S (991.2)
2017-2019
Turbocharged 3.0L producing 370-420 hp. More power everywhere but different character.
Desirability:
High
Carrera 4 / 4S
2012-2019
All-wheel drive variants. Widebody styling standard on 4S. More stable in all conditions.
Desirability:
High
GT3 / GT3 RS
2014-2019
Track-focused with naturally aspirated 4.0L producing 475-520 hp. PDK or manual available. Exceptional drivers' cars.
Desirability:
High
Turbo / Turbo S
2014-2019
Twin-turbo with 520-580 hp. AWD standard. Incredible straight-line performance with daily usability.
Desirability:
High
GT2 RS
2018-2019
The ultimate 991 with 700 hp from twin-turbo 3.8L. Rear-wheel drive, track weapon. Highly collectible.
Desirability:
High
Targa 4 / 4S
2014-2019
Distinctive power-operated Targa top with AWD. Elegant and practical.
Desirability:
High
Pre-Purchase Inspection Checklist
Critical areas to examine before purchasing. Bring this checklist when viewing a 991.
Engine
-
Oil Consumption
991 engines can consume some oil, especially when driven hard. Monitor levels.
If bad: Monitor and maintain
-
Turbo Condition (991.2/Turbo)
Check for boost leaks, wastegate operation, and proper boost pressure.
If bad: $3,000-8,000
-
Coolant System
Check expansion tank and radiators for leaks. Overheating is engine-critical.
If bad: $500-1,500
-
Engine Mounts
Can wear on higher-mileage cars causing vibration.
If bad: $600-1,200
Transmission
-
PDK Operation
Most 991s have PDK. Check for smooth operation, proper clutch wear indication.
If bad: $2,000-6,000
-
Manual Transmission
If equipped, test all gears. Check for synchro wear on high-mileage cars.
If bad: $2,000-4,000
-
PDK Fluid Service
Verify PDK fluid has been serviced at proper intervals.
If bad: $500-800 for service
Suspension & Brakes
-
PASM Shocks
Most 991s have PASM. Test in all modes for proper damping.
If bad: $3,000-6,000
-
PCCB Brakes
If equipped with ceramic brakes, check rotor condition carefully. Extremely expensive to replace.
If bad: $15,000-25,000
-
Control Arm Bushings
Can wear on track-driven or high-mileage cars.
If bad: $800-1,500
-
Rear Axle Steering (if equipped)
Test for proper operation. Complex system.
If bad: $2,000-4,000
Electrical & Technology
-
PCM System
Test navigation, connectivity, and all infotainment functions.
If bad: $1,000-3,000
-
Sport Chrono
If equipped, verify all modes function including launch control.
If bad: $500-1,500
-
Convertible/Targa Top
Test full operation. Targa mechanism is complex.
If bad: $2,000-5,000
Body
-
Paint Condition
Check for rock chips, especially on front fascia. Clear bra recommended.
If bad: $500-3,000
-
Wheel Condition
Check for curb rash. Factory wheels are expensive to replace.
If bad: $500-2,000 per wheel
-
Accident History
Check panels for consistent gaps and paint matching.
If bad: Varies significantly
Pricing Guide
Prices as of 2026. Values vary by location, options, and market conditions.
Project Car
$50,000 - $70,000
Higher-mileage base Carreras or cars with service needs.
Driver Quality
$70,000 - $100,000
Good Carrera S or 4S examples with reasonable miles.
Excellent
$100,000 - $180,000
Well-maintained GT3, Turbo, or low-mileage GTS examples.
Concours / Collector
$180,000 - $450,000+
GT3 RS, GT2 RS, or exceptional low-mileage special editions.
Red Flags - Walk Away If...
- PCCB brakes with visible damage or excessive wear
- Evidence of track abuse without proper maintenance
- Salvage or rebuilt title
- PDK with shudder or transmission codes
- Missing service documentation
- Aftermarket tune without supporting modifications
- GT cars with questionable racing history
What to Look For
Desirable features and options that add value:
- Carrera S or GTS for best all-around package
- 991.1 for naturally aspirated character
- 991.2 for more everyday power
- GT3 manual for ultimate driver engagement
- Complete Porsche service documentation
- Sport Chrono and PASM as standard equipment
- Avoid PCCB unless budget allows for replacement
- Factory CPO warranty if still applicable
Ownership Costs
Insurance
$2,000-4,000/year
Annual Maintenance
$1,500-3,500 for regular service
Common Repairs
$1,000-2,500/year typical
Fuel Economy
19-25 MPG
Expert Tips
- The 991 is one of the most refined and capable 911s ever made
- 991.1 naturally aspirated engines are preferred by purists
- 991.2 turbo engines offer better everyday performance
- GT3 with manual transmission is the enthusiast's choice
- Avoid PCCB ceramic brakes if you can't afford replacement
- PDK is faster but manual is more engaging
- Factory CPO warranty provides excellent peace of mind
- Budget for proper maintenance - these are complex cars
- The 991 is reliable with proper care
- GT2 RS and GT3 RS are appreciating collectibles
Common Issues
Known problems, symptoms, and solutions for the 991 platform
Symptoms: Coolant loss, overheating warning, coolant puddles, sweet smell, temperature fluctuation
The 991 continues to use plastic coolant pipes in the cooling system. These pipes run from the front radiators to the rear engine and are subjected to heat cycling and vibration. They can crack, especially at connection points, causing coolant loss. The coolant transfer pipe in particular is a known failure point.
Estimated Repair Costs
DIY
$200-400
Shop
$500-1000
Continues plastic pipe tradition. Aluminum upgrades available.
Common Fixes
- Replace plastic coolant pipes with aluminum upgrade
- Coolant transfer pipe replacement (common failure)
- Replace expansion tank if showing age
- Water pump replacement as preventive maintenance
- Flush and refill with proper coolant mix
Common Parts
| Part |
Part Number |
Est. Price |
| Coolant Transfer Pipe |
99110663701 |
$100-200 |
| Coolant Pipe Kit (Aluminum) |
Various |
$200-400 |
Symptoms: Rough idle, misfires, reduced power, poor fuel economy, hesitation under load
All 991 engines use direct fuel injection (DFI), meaning fuel doesn't wash over the intake valves. Carbon deposits accumulate on the valve backs and intake ports, restricting airflow and affecting engine performance. This is a maintenance item requiring periodic walnut blasting, typically every 50,000-80,000 miles depending on driving style.
Estimated Repair Costs
DIY
$200-400
Shop
$500-1000
All 991 engines are DFI. Walnut blasting needed periodically.
Common Fixes
- Walnut shell blasting (standard solution)
- Chemical treatments (less invasive but less effective)
- Catch can installation to reduce oil vapor deposits
- Use Top Tier fuel with good detergent packages
- Spirited driving helps but doesn't eliminate buildup
Common Parts
| Part |
Part Number |
Est. Price |
| Walnut Media |
N/A |
$30-50 |
| Intake Gaskets |
9A111024900 |
$25-50 |
Symptoms: Harsh shifts, jerky low-speed operation, shuddering, warning lights, delayed engagement
The PDK dual-clutch transmission is generally reliable but can develop issues. Low-speed jerkiness, especially when cold, is common and may be normal for the system. More serious issues include clutch pack wear, mechatronic unit failures, and software glitches. PDK fluid should be serviced despite Porsche's 'lifetime' fill claim.
Estimated Repair Costs
DIY
$150-250
Shop
$400-2000+
Fluid service recommended every 50-60k despite 'lifetime' fill.
Common Fixes
- PDK fluid change (recommended every 50,000-60,000 miles)
- Software updates to address shift quality
- Clutch adaptation reset via PIWIS diagnostic
- Clutch pack replacement if severely worn
- Mechatronic unit repair for electronic issues
Common Parts
| Part |
Part Number |
Est. Price |
| PDK Fluid (7L) |
Pentosin FFL-2 |
$150-200 |
| PDK Filter |
9G132153300 |
$40-80 |
Symptoms: PASM warning light, harsh ride, damper leaking, clunking noises, uneven handling
PASM (Porsche Active Suspension Management) dampers use electronic valving to adjust stiffness. These dampers can fail, usually by leaking or developing electrical issues. A failed damper triggers a warning light and the system may default to a fixed setting. PASM dampers are expensive compared to conventional shocks.
Estimated Repair Costs
DIY
$400-800
Shop
$800-1500
Electronic dampers fail. Remanufactured available.
Common Fixes
- Diagnose with Porsche diagnostic tool (PIWIS)
- Replace failed PASM damper (OEM or remanufactured)
- Some owners convert to quality coilovers when multiple fail
- Check wiring and connectors before replacing damper
- Remanufactured dampers available at reduced cost
Common Parts
| Part |
Part Number |
Est. Price |
| PASM Damper (Front) |
99134305315 |
$600-1000 |
| PASM Damper (Rear) |
99133305316 |
$600-1000 |
| PASM (Remanufactured) |
Various |
$350-550 |
Symptoms: Low oil warnings, need to add oil between changes, blue smoke on startup, oil smell
Some 991.1 models exhibit higher than expected oil consumption. Porsche's stated acceptable consumption is up to 1 quart per 1,000 miles, which many owners find excessive. Direct injection, high compression, and tight tolerances contribute. Tracking oil level is important, and the car should not be run low on oil.
Estimated Repair Costs
DIY
$50-100
Shop
$100-500
991.1 may consume oil. Monitor and top up. Severe cases need diagnosis.
Common Fixes
- Monitor oil level regularly using on-board system
- Keep oil level in proper range (not overfilled)
- Some owners report improvement with different oil brands
- Severe consumption may indicate piston ring issues
- Compression and leak-down test for diagnosis
Common Parts
| Part |
Part Number |
Est. Price |
| Engine Oil (10L) |
Mobil 1 0W-40 |
$80-120 |
| Oil Filter |
99110722553 |
$20-40 |
Symptoms: Boost inconsistency, wastegate rattle, turbo whine, check engine light, reduced power
The 991.2 moved to twin-turbo engines for all models. While generally reliable, the turbos can develop issues including wastegate rattle, actuator problems, and seal failures. Turbo feed and drain lines need monitoring. These engines are more complex than the naturally aspirated 991.1.
Estimated Repair Costs
DIY
$100-300
Shop
$500-2000+
991.2 twin-turbo. Wastegate rattle and boost issues.
Common Fixes
- Wastegate actuator adjustment or replacement
- Turbo oil line inspection and replacement
- Intercooler inspection for leaks
- Boost leak testing if low power complaints
- Proper warm-up and cool-down for turbo longevity
Common Parts
| Part |
Part Number |
Est. Price |
| Wastegate Actuator |
9A112180101 |
$300-500 |
| Turbo Oil Line Kit |
Various |
$100-200 |
Symptoms: Slow operation, error messages, hydraulic leaks, top doesn't complete cycle, fabric wear
The 991 Cabriolet's power top system is complex and can develop age-related issues. Hydraulic pump wear, microswitch failures, and ram seal leaks cause operational problems. The fabric top can wear at stress points, and the rear window can develop issues. Proper operation and storage help longevity.
Estimated Repair Costs
DIY
$100-400
Shop
$500-1500
Cabriolet only. Complex hydraulic system.
Common Fixes
- Hydraulic system inspection and fluid top-off
- Hydraulic pump replacement if failing
- Microswitch adjustment or replacement
- Top fabric replacement for worn or damaged tops
- System reset procedure after battery work
Common Parts
| Part |
Part Number |
Est. Price |
| Hydraulic Pump |
99156160901 |
$500-800 |
| Microswitch Kit |
Various |
$50-100 |
Symptoms: Creaking noise, steering feel inconsistency, steering wheel off-center, warning lights
The 991 uses an electric power steering system. While generally reliable, some owners report issues with the steering column producing creaking noises, especially when turning at low speeds. There can also be software-related issues affecting steering feel or causing warning messages.
Estimated Repair Costs
DIY
$50-150
Shop
$200-500
Creaking from column. Lubrication often helps.
Common Fixes
- Steering column lubrication for creaking
- Software update for steering feel issues
- Steering rack inspection if play detected
- Steering angle sensor recalibration
- Full diagnosis with Porsche diagnostic tool
Common Parts
| Part |
Part Number |
Est. Price |
| Steering Column Lube |
Various |
$15-30 |
| Steering Angle Sensor |
99136115500 |
$200-350 |
