2008 PONTIAC G5

Typical onset: 80,000-130,000 mi

Symptoms: rattling on cold start that disappears after warmup, sudden loss of oil pressure, metallic grinding from engine bay, check engine light with timing codes, catastrophic engine seizure without warning

Fix: The timing chain tensioner and guides wear prematurely, and the balance shaft drive system fails, starving the engine of oil. Once the chain jumps or balance shaft seizes, you're looking at complete engine replacement or rebuild. Timing chain job alone is 8-10 hours, but most engines are too damaged by the time symptoms appear. Short block replacement is 12-16 hours.

Estimated cost: $3,500-6,500

Typical onset: 60,000-100,000 mi

Symptoms: intermittent loss of power steering, grinding or whining noise from steering column, complete steering assist loss at any speed, service power steering warning, heavy steering requiring significant force

Fix: The EPS motor and control module fail, often suddenly while driving. This was recalled but many units still fail post-recall. Replacement of the entire steering column assembly is typical. 3-4 hours labor. This is a serious safety issue when it fails at highway speeds.

Estimated cost: $800-1,400

Symptoms: engine stalls while driving, all electrical accessories cut out suddenly, key gets stuck in ignition, won't start intermittently, airbags may not deploy in crash

Fix: Part of GM's infamous ignition switch recall, the switch contacts wear and allow the key to rotate out of RUN position. This kills the engine, power steering, power brakes, and disables airbags. Even recalled switches can fail. Replacement is 1-1.5 hours but requires GM-specific reprogramming of passlock system.

Estimated cost: $250-450

Typical onset: 70,000-110,000 mi

Symptoms: transmission fluid puddle under engine bay, pink fluid mixing with coolant in overflow, transmission overheating, slipping or harsh shifts, milky transmission fluid on dipstick

Fix: The transmission cooler lines rust through where they connect to the radiator, and the internal cooler inside the radiator fails, allowing coolant and ATF to mix. This destroys the transmission if not caught early. Requires cooler line replacement (2 hours) or radiator replacement plus complete fluid flush (3-4 hours). If coolant contaminated the trans, expect rebuild.

Estimated cost: $400-800 for lines/radiator, $2,000-3,500 if transmission damaged

Typical onset: 90,000-140,000 mi

Symptoms: no start condition, engine cranks but won't fire, loss of power under acceleration, sputtering at highway speeds, whining noise from fuel tank

Fix: The in-tank fuel pump assembly fails, often stranding the vehicle. Diagnosis requires fuel pressure test. Replacement involves dropping the fuel tank. 2-3 hours labor. Sometimes just the pump, sometimes the entire sending unit assembly.

Estimated cost: $500-900

Typical onset: 60,000-100,000 mi

Symptoms: clunking when shifting into drive or reverse, excessive vibration at idle, visible engine movement when revving, banging noise over bumps

Fix: The front transmission mount (also called torque strut) tears and collapses due to poor rubber compound. Creates harsh shifting feel and allows powertrain to rock excessively. Easy fix at 1-1.5 hours but often ignored until it's completely separated.

Estimated cost: $150-300

Typical onset: 80,000-120,000 mi

Symptoms: rough idle, check engine light with lean codes, loss of power, whistling or hissing from intake, poor fuel economy

Fix: The 2.4L has variable intake runner valves that stick and fail, and the manifold gaskets leak vacuum. Requires intake manifold removal and cleaning of carbon buildup on valves or full manifold replacement. 3-4 hours labor.

Estimated cost: $400-700