2011 Chevrolet Hhr

The electric power steering (EPS) system fails without warning, causing a sudden and complete loss of power assist. The 'Power Steering' warning light illuminates and the steering wheel becomes extremely difficult to turn. This is the most commonly reported safety complaint on the HHR and is especially dangerous during low-speed maneuvers like parking or turning at intersections.

Replace the electric power steering motor and/or the EPS control module. GM issued TSB 09-02-35-001E addressing EPS failures on the HHR. The motor is located on the steering column. Flash the replacement module with the latest calibration. In some cases, the wiring harness connector to the EPS motor also needs replacement due to heat damage.

The HHR shares the same defective ignition switch as the Cobalt and other GM small cars. The switch can rotate out of the 'Run' position while driving, shutting off the engine and disabling power steering, power brakes, and airbags. This defect is particularly dangerous as it removes multiple safety systems simultaneously and was linked to numerous fatalities.

NHTSA Recall 14V047000. GM replaced the ignition switch and reprogrammed the airbag module on all affected vehicles free of charge. Contact a Chevrolet dealer to confirm the recall has been completed on your vehicle, as some remain unrepaired.

The Ecotec four-cylinder engine develops timing chain stretch and timing chain guide wear over time. Owners notice a metallic rattling noise on cold starts that may persist as the engine warms up. Advanced chain stretch causes the check engine light with timing correlation codes (P0016, P0017) and can lead to rough running, misfires, and eventual engine damage if the chain skips.

Replace the timing chain, hydraulic tensioner, and all chain guides as a set. The repair requires removing the front engine cover and timing cover. Updated tensioner and guide designs are available. Ensure proper oil change intervals are maintained, as oil degradation accelerates chain and guide wear.

The 2.4L Ecotec engine in the HHR is prone to head gasket failure, which allows coolant to leak into the combustion chambers or externally. Symptoms include white smoke from the exhaust, coolant loss with no visible external leak, milky residue on the oil fill cap, overheating, and engine misfires. The issue is accelerated by overheating episodes from other cooling system failures.

Replace the head gasket, have the cylinder head inspected and resurfaced at a machine shop, and replace the head bolts with new torque-to-yield bolts. Flush the cooling system and replace the thermostat. Inspect the engine oil for coolant contamination and change it immediately after repair.

The catalytic converter fails prematurely, triggering check engine light codes P0420 (Catalyst System Efficiency Below Threshold). Owners report the check engine light coming on between 60,000 and 100,000 miles. Failed converters can cause reduced engine performance, poor fuel economy, and a sulfur (rotten egg) smell from the exhaust.

Replace the catalytic converter. Use a CARB-compliant converter if the vehicle is registered in a state with enhanced emissions testing. The exhaust manifold and catalytic converter are a combined unit on some HHR configurations, increasing the replacement cost. Inspect upstream oxygen sensors and replace if needed to protect the new converter.