The 2004 Scion xA is a rebadged first-generation Toyota bB with Toyota's 1NZ-FE 1.5L engine and a four-speed automatic or five-speed manual. Generally reliable transport, but this specific model year saw oil consumption issues that can grenade engines if ignored, plus typical automatic transmission cooler line failures.
Catastrophic Oil Consumption / Piston Ring Failure
Common · high severityTypical onset: 80,000-150,000 mi
Symptoms: Blue smoke on cold start or acceleration, Oil level drops a quart every 500-1,000 miles, Check engine light with misfire codes (P0301-P0304), Sudden loss of power, knocking noise if run low on oil
Fix: The 1NZ-FE in this era suffers from piston ring land cracking and carbon buildup causing rings to stick. Real fix requires engine rebuild with updated pistons and rings (12-16 hours labor) or used/reman short block swap (10-14 hours). Band-aid approach is top-end teardown and manual ring cleaning, but it returns within 20k miles.
Estimated cost: $2,800-4,500
Automatic Transmission Oil Cooler Line Rupture
Common · high severityTypical onset: 100,000-180,000 mi
Symptoms: Red fluid pooling under engine bay, driver side, Transmission slipping or not engaging after fluid loss, Sweet burnt smell near radiator, Low transmission fluid on dipstick
Fix: The steel cooler lines rust through where they mount near the radiator. Line replacement is straightforward (2-3 hours), but if the trans ran low, internal damage may already be done. Always replace both lines and flush the system. Manual transmission cars don't have this issue.
Estimated cost: $350-600
Transmission Mount Collapse (Automatic)
Common · medium severityTypical onset: 70,000-130,000 mi
Symptoms: Clunk on hard acceleration or deceleration, Excessive vibration at idle in Drive, Visible engine movement when revving in Park, Transmission shifts feel harsher
Fix: The rear transmission mount (actually engine torque mount) is hydraulic-filled and fails predictably. Requires lifting the engine slightly, 1.5-2 hours labor. OEM part is best; aftermarket units often fail within a year.
Estimated cost: $220-380
Fuel Filter Clogging (Pre-Pump Strainer)
Occasional · medium severityTypical onset: 120,000+ mi
Symptoms: Hard start after sitting overnight, Loss of power on highway acceleration, Intermittent stalling, especially in hot weather, Fuel pump whine becomes louder
Fix: The in-tank strainer clogs with sediment, starving the pump. Requires tank drop and pump assembly removal (3-4 hours). Toyota doesn't sell the strainer separately, so you're replacing the whole pump assembly or carefully cleaning the OEM strainer if it's not cracked.
Estimated cost: $450-750
Dashboard Rattles and Trim Failures
Common · low severityTypical onset: 60,000+ mi
Symptoms: Persistent rattle from center console or upper dash, Door panel clips break, panels sag, Glove box door won't latch properly, Plastic trim around shifter cracks
Fix: Interior plastics are economy-grade and develop annoying squeaks. Most owners live with it or apply felt tape. Proper fix involves removing panels, replacing clips, and applying damping material (2-4 hours if done right, but rarely worth paying a shop).
Estimated cost: $150-300
Airbag Control Module Recall Compliance
Occasional · high severitySymptoms: Airbag warning light stays on, No airbag deployment in actual collision (worst case), SRS codes stored in module
Fix: NHTSA recall for airbag control module — if not already completed, verify recall status by VIN. Dealer handles this at no cost. If the light is on and recall was done, could be clockspring or seat belt pretensioner (1-2 hours diagnosis, 2-3 hours repair depending on component).
Estimated cost: $0 (recall) or $300-650 (post-recall issues)
Buy a manual transmission example under 100k miles with documented oil change history, or budget for an engine rebuild on any high-miler — otherwise a solid commuter that's cheap to own if you dodge the oil consumption curse.
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.