2015 Chevrolet Impala engine problems
severe 14 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
The failure pattern owners describe
Buyer takeaway: 2015 Impala owners report recurring engine control issues—purge solenoid faults causing surge, catalytic converter welds cracking at low miles, and rocker arm valve failures with discontinued parts. Fuel system corrosion under E85 and intermittent stalling add to reliability concerns.
Owners describe a pattern of engine management and fuel system problems. The most common failure centers on EVAP purge control components: a stuck-open purge solenoid caused one owner's vehicle to surge forward while parked (29,000 miles), and subsequent Check Engine lights occurred after dealer repair. GM issued a service letter in July 2018 addressing purge solenoid protection but only reimbursed one of two related repairs.
Catalytic converter mounting welds separate from the engine at the flange, dropping the converter into the cooling fan and requiring engine replacement (136,000 miles). GM issued TSB PIP5419a & b in 2016 documenting this weld-crack defect across all 2014-2016 Impalas with 3.6L engines, but no recall followed.
Rocker arm oil control valve failures create a parts availability crisis: owners at 104,928 miles encountered low oil pressure warnings and oil leaks, and GM has discontinued the replacement part for 2014-2015 models, leaving vehicles unfixable. Owners report being forced to trade in vehicles they are still financing.
Engine stalling occurs with minimal warning across various speeds, sometimes requiring tow. One owner using E85 fuel (per owner's manual recommendation) faced fuel pump and feed pipe corrosion that GM refused to cover. A variable timing oil control valve fault (code P16CF) caused high RPM surging during acceleration. One vehicle caught fire while parked at 172,000 miles with suspected mechanical cause.
Same Chevrolet Impala engine reports on nearby years: 2012 · 2014 · 2017
Failure modes owners describe
Purge solenoid stuck open / EVAP system failure
Purge control solenoid or EVAP canister vent valve solenoid malfunction causing unwanted engine idle increase, vehicle surge, and Check Engine light.
When: 29,000 miles; also reported at 3 months prior to July 2018 service letter
Symptoms owners cite: Vehicle surges forward unexpectedly while parked with brake applied; Engine revving to 3,000 RPM requiring both feet on brake; Check Engine light illumination; Abnormal idle behavior
Codes mentioned: EVAP canister vent valve solenoid fault, Purge valve fault
Repairs/costs cited: EVAP canister vent valve solenoid replacement ($198.77); purge valve replacement ($147.55); vehicle repaired by dealer
Recalls/TSBs owners mention: July 2018 service letter issued offering additional protection; partial reimbursement approved for purge valve repair but not EVAP canister vent valve
Catalytic converter weld failure and separation
Catalytic converter mounting weld cracks and fails, causing the converter to separate from engine at the mounting flange and damage cooling fan.
When: 136,000 miles; also ~104,928 miles (rocker arm issue alongside); failure reported across 2014-2016 model years
Symptoms owners cite: Loud clanking sound from engine; Abnormal gasoline odor; Gasoline leak from engine compartment; Catalytic converter visibly detached at mounting flange
Repairs/costs cited: Diagnosis: catalytic converter failure requiring engine replacement; vehicle not repaired. Aftermarket replacement parts available
Recalls/TSBs owners mention: TSB PIP5419a & b issued 2016 for 2014-2016 Impalas (all VINs, 3.6L LFX engines) documenting weld crack defect; no recall issued; GM stated 'working on a solution'
Engine stalling without warning
Complete loss of engine operation while driving at low and highway speeds, sometimes with immediate restart but occasionally requiring tow. No warning lights in some cases.
When: 60,000 miles (rear-end collision incident); 212,000 miles (intermittent stalling)
Symptoms owners cite: Complete engine stall at 25 MPH and various speeds; Vehicle coasts to stop unpowered; Intermittent stalling with independent restart while rolling; Stalling without warning light illumination; One incident required both feet on brake after restart
Repairs/costs cited: Battery replacement performed at one dealership; other dealers unable to duplicate or diagnose; vehicles not repaired
Recalls/TSBs owners mention: No manufacturer notification or response documented in narratives
Rocker arm oil control valve failure
Rocker arm oil control valve degrades or fails, causing oil system malfunction. Parts obsolescence issue: GM discontinued production of replacement part for 2014-2015 models, leaving owners unable to repair vehicles.
When: 104,928 miles initially; recurring failures reported shortly after first replacement
Symptoms owners cite: Smoke from under hood while driving; Oil leaking from engine; Low oil pressure warning light illumination; Repeat failures of replacement parts
Repairs/costs cited: Rocker arm oil control valve replacement required; parts reported on back order and subsequently discontinued by manufacturer. Owners report being unable to obtain parts and forced to trade in vehicles
Recalls/TSBs owners mention: GM discontinued production of rocker arm oil control valve for 2014-2015 models; no communication to owners or timeline for resolution
High-pressure fuel pump and fuel feed pipe corrosion (E85 fuel)
High-pressure fuel pump and fuel feed pipe corrode and fail when using E85 ethanol blend fuel, despite owner's manual recommending E85 compatibility. Results in service warnings and power loss.
When: Unspecified mileage at time of service visit
Symptoms owners cite: Dashboard service messages: 'SERVICE STABIL A TRACK', 'SERVICE TRACTION CONTROL', 'POWER TO ENGINE REDUCED'; Service Engine light illumination
Repairs/costs cited: Diagnosis: high-pressure fuel pump and fuel feed pipe replacement needed; owner not reimbursed by GM despite following owner's manual E85 fuel recommendation
Recalls/TSBs owners mention: GM refused to pay for repairs; dealership confirmed E85 fuel causes damage in Chevrolet vehicles and contradicts owner's manual recommendation
Variable timing oil control valve fault
Variable timing oil control valve malfunction causing erratic engine behavior during acceleration and Check Engine light.
When: Unspecified mileage
Symptoms owners cite: Engine revs to excessively high RPMs during acceleration; Loss of power to wheels, especially when accelerating to pass at 50+ MPH; Check Engine light illumination
Codes mentioned: P16CF
Engine compartment fire
Vehicle caught fire while parked and unoccupied. Fire department indicated mechanical malfunction as likely cause. Vehicle completely consumed and destroyed.
When: 172,000 miles
Symptoms owners cite: Front of vehicle erupted in fire while parked, turned off, unoccupied
Repairs/costs cited: Vehicle destroyed; no diagnosis or repair performed
Recalls/TSBs owners mention: Manufacturer not notified; no investigation documented
Synthesized from 14 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 0 most recent
Common questions
How serious is the engine problem on the 2015 Chevrolet Impala?
It's a meaningful issue. 14 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $3,100.
At what mileage does the engine typically fail?
Across the 12 complaints that reported odometer mileage, most engine failures cluster between 45,000 and 136,000 miles, with the median around 89,000. A quarter of owners report trouble before 45,000; a quarter make it past 136,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.