The 2017 A45 AMG packs the M133 2.0L turbo four making 375+ hp in a compact platform—impressive performance but notorious for catastrophic engine failures when pushed hard or inadequately maintained. The 7-speed DCT is generally robust but has specific weak points that show up with age.
M133 Engine Connecting Rod Bearing Failure (Rod Knock)
Occasional · high severity
Typical onset: 40,000-80,000 mi
Symptoms: Knocking/tapping noise from engine bay especially on cold start or under load, Metallic rattling that worsens with RPM, Low oil pressure warnings in severe cases, Metal shavings visible in oil during changes
Fix: This is the big one—rod bearings fail prematurely on M133 engines, especially those tracked or driven hard. Fix requires full engine-out rebuild with upgraded bearings, crank inspection/machining, new pistons/rings typically included. 25-35 labor hours for engine removal, teardown, machine work, reassembly. Many owners go straight to short block replacement to avoid re-failure.
Estimated cost: $8,000-15,000
Piston Ring Land Cracking and Cylinder Scoring
Occasional · high severity
Typical onset: 50,000-90,000 mi
Symptoms: Excessive oil consumption (1 qt per 1,000 miles or worse), Blue smoke from exhaust on startup or acceleration, Loss of compression in one or more cylinders, Misfires and rough idle, Fuel smell in oil
Fix: The M133 runs aggressive boost and timing—piston ring lands crack under stress, allowing blow-by and oil consumption. Requires cylinder head removal, honing or bore/re-sleeve if scoring is severe, new pistons and rings. Often done alongside rod bearing service. 20-30 labor hours depending on cylinder condition.
Estimated cost: $6,500-12,000
Head Gasket Failure (Both)
Rare · high severity
Typical onset: 60,000-100,000 mi
Symptoms: Coolant loss with no external leaks, White smoke from exhaust, Overheating or erratic temperature gauge, Milky oil or oil in coolant reservoir, Rough idle and misfires
Fix: Less common than rod/piston issues but still occurs, especially on tuned cars or those with cooling system neglect. Head removal, machining/resurfacing, new gaskets, ARP studs recommended. 18-24 labor hours. Often combined with timing chain inspection while heads are off.
Estimated cost: $4,500-7,500
DCT Transmission Oil Cooler Leaks
Common · medium severity
Typical onset: 50,000-90,000 mi
Symptoms: Transmission fluid puddles under car (red/pink fluid), Burnt transmission smell, Harsh shifts or delayed engagement when fluid is low, Transmission temperature warnings on display
Fix: The external transmission oil cooler develops leaks at seals and fittings. Cooler replacement is straightforward—drop undertray, drain fluid, unbolt cooler lines, swap unit. 2-3 labor hours. Critical to catch early before low fluid damages clutch packs.
Estimated cost: $800-1,400
Transmission Mount Deterioration
Common · low severity
Typical onset: 60,000-100,000 mi
Symptoms: Clunking during shifts, especially 1-2 and 2-3, Excessive drivetrain movement when launching or engine braking, Vibration through cabin at idle in gear, Visible tearing or separation of rubber mount
Fix: The hydraulic transmission mount wears out from the DCT's aggressive shifts and high torque. Simple replacement—lift car, support trans, unbolt old mount, install new OEM or upgraded unit. 1.5-2 labor hours.
Estimated cost: $400-700
High-Pressure Fuel Pump Failure
Occasional · medium severity
Typical onset: 70,000-110,000 mi
Symptoms: Hard starting or extended cranking, Rough idle and hesitation under load, Fuel pressure codes (P0087, P228C), Limp mode activation, Whining noise from engine bay
Fix: The high-pressure fuel pump (mounted on engine) fails internally or seals leak. Replacement requires removal of intake components for access. Also replace fuel filter during service. 3-4 labor hours.
Estimated cost: $1,200-2,000
Owner tips
Change oil every 5,000 miles maximum with quality 5W-40 full synthetic—extended intervals kill rod bearings on this engine
Monitor oil consumption religiously; if burning more than 1 qt per 3,000 miles, inspect immediately
DCT fluid should be changed every 40,000 miles despite 'lifetime fill' claims—keeps shifts smooth and prevents clutch pack wear
Avoid sustained high-RPM use until oil is fully warmed; cold-start abuse accelerates piston ring land cracking
Budget $1,000/year maintenance minimum; these are high-strung AMG engines that demand attention
Buy only with full service records and oil analysis showing clean engine—these are spectacular when healthy but catastrophic engine failures make high-mileage examples a $10K+ gamble.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
Fitment notes: Battery located in trunk under floor panel; high-performance AGM required for AMG model with start-stop system
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Every control module on the 2014-2018 Mercedes-Benz A45 AMG W176 — where it lives, replacement time, and what it takes to program a replacement. Modules marked dealer / factory tool won't work after a part swap alone — budget for programming.
Electric Power Steering Control Unit (EPS)2.5 hr R&Rdealer / factory tool +1.0 hr▸ programming details
⚠️ mbrace services. Requires subscription activation after replacement.
Rear View Camera Control Unit (RVC)0.5 hr R&Raftermarket tool +0.2 hr▸ programming details
📍 Tailgate, integrated with camera assembly
🔧 Xentry Diagnostics or Autel MaxiSys
⚠️ Camera alignment may be required. Basic coding accessible to aftermarket tools.
Aftermarket tool coverage varies by software version and vehicle build — treat "aftermarket tool" rows as "usually possible" and verify against your tool maker's coverage list before promising a customer. Spot a wrong location or hour? Tell us — corrections ship fast here.
Size-standard part numbers — verify your connector type before buying. Rear blades are model-specific; check the package's vehicle list.
Fuel economy figures are EPA data via fueleconomy.gov (median across matching trims). Performance figures are compiled estimates for the 2017 Mercedes-Benz A45 AMG W176 2.0L I4 Turbo M133 and can vary by trim.
🔧 Database maintained under the daily editorial review of Chris Hackleman · Master Technician · 20+ years and Jeff Moore · Master Lexus & Toyota Mechanic · 20+ years.