The 2004 Scion xB (1NZ-FE 1.5L) is generally reliable but has one catastrophic weakness: oil consumption from piston ring failure leads to engine death if ignored. Transmissions are solid, but oil cooler leaks and motor mounts are routine maintenance items on high-mileage examples.
Excessive Oil Consumption / Piston Ring Failure (1NZ-FE)
Common · high severity
Typical onset: 120,000-180,000 mi
Symptoms: Burning a quart of oil every 500-1,000 miles, Blue smoke on cold start or heavy acceleration, Fouled spark plugs (carbon buildup), Check engine light for misfire codes (P0301-P0304), Low compression readings cylinder 2 or 3 most common
Fix: Rings wear due to carbon buildup in oil control ring grooves—catch-can helps but doesn't cure it. Once symptomatic, you're looking at rings/pistons or shortblock. Ring job requires full teardown, hone, new bearings: 16-20 hours. Shortblock swap if bearings are scored: 18-22 hours. Many shops won't do rings-only on high-mileage 1NZ due to labor overlap with full rebuild.
Estimated cost: $2,800-4,500
Transmission Oil Cooler Line Leaks
Common · medium severity
Typical onset: 100,000-150,000 mi
Symptoms: ATF puddles under front of engine bay, driver side, Trans fluid level dropping between services, Burnt ATF smell if driven low on fluid, Pink/red fluid mixing with coolant if internal cooler fails (rare but catastrophic)
Fix: Steel lines rust at crimp joints and fittings. Replace both feed and return lines as a pair—one fails, the other is close behind. 2.5-3.5 hours. If the internal radiator cooler fails (crossover contamination), you're flushing the trans and replacing the radiator, adding 4-5 hours total.
Estimated cost: $350-650
Front and Rear Transmission Mounts Collapse
Common · low severity
Typical onset: 80,000-130,000 mi
Symptoms: Clunk on hard acceleration or deceleration, Vibration at idle in Drive, Shifter clunk when moving from Park to Drive, Visible engine rocking when revving in Park
Fix: Rubber degrades and the hydraulic mounts lose fluid. Replace front and rear trans mounts together—rear mount requires subframe support. 2.5-3 hours. Do not ignore; excessive movement can crack exhaust or stress axle boots.
Estimated cost: $400-600
Fuel Filter Clogging (In-Tank Sock and Inline)
Occasional · medium severity
Typical onset: 90,000-140,000 mi
Symptoms: Stumble or hesitation under load, especially uphill, Hard starting after sitting overnight, Fuel pressure below spec (38-44 psi at idle), Check engine light for lean codes (P0171/P0174)
Fix: Toyota spec calls for inline filter replacement every 60k but many skip it. Sock filter in the pump assembly also clogs from tank sediment. Inline filter: 0.5 hour. In-tank pump/sock assembly: drop tank, 3-4 hours. If you're doing the in-tank, replace the whole pump module—labor is the killer.
Symptoms: Headlights flickering or cutting out intermittently, Burnt plastic smell near headlight assemblies, Melted connector at headlight bulb socket, One or both low beams inoperative
Fix: Factory halogen bulbs run hot; aftermarket high-wattage bulbs make it worse. NHTSA recall addressed some VINs but not all. Repair: replace headlight pigtail connectors and upgrade to relays with dedicated power feed. 1.5-2 hours if done right with relay harness; 0.5 hour for OEM pigtail-only bandaid.
Estimated cost: $150-400
Cruise Control Actuator Cable Binding
Rare · low severity
Typical onset: 100,000+ mi
Symptoms: Cruise control won't engage or surges, Throttle sticks slightly after cruise is canceled, Cable visible fraying at actuator pulley
Fix: Cable-driven cruise actuator on firewall—cable corrodes or binds in housing. Replace actuator and cable as assembly. 1.5 hours. Recall 06V281000 covered some units for unintended acceleration risk; check VIN eligibility.
Estimated cost: $250-450
Owner tips
Check oil every 1,000 miles religiously after 100k—this engine will eat itself if run low
Install an oil catch-can early (before 80k) to slow piston ring clogging; use Toyota 0W-20 only
Inspect trans cooler lines annually in rust belt states; replace at first sign of surface rust
Stick to OEM-equivalent headlight bulbs (55W max); higher wattage kills the wiring
Don't skip the inline fuel filter at 60k and 120k—cheap insurance against pump failure
Buy it if the engine doesn't smoke and the seller has oil-change records—great city box, but the 1NZ oil consumption is a ticking time bomb without vigilant monitoring.
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.
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DOPE, INC. IS RECALLING 42,540 COMBINATION CORNER AND BUMPER LAMP ASSEMBLIES OF VARIOUS PART NUMBERS SOLD FOR USE AS AFTERMARKET EQUIPMENT FOR VARIOUS PASSENGER VEHICLES. THESE HEADLAMPS FAIL TO CONFORM TO THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 108, "LAMPS, REFLECTIVE DEVICES, AND ASSOCIATED EQUIPMENT." THESE LAMPS DO NOT CONTAIN THE REQUIRED AMBER SIDE REFLECTORS.
Consequence: DECREASED LIGHTING VISIBILITY MAY RESULT IN A VEHICLE CRASH.
Remedy: DOPE, INC. WILL NOTIFY OWNERS AND OFFER A FULL REFUND FOR THE NONCOMPLIANT COMBINATION LAMPS. THE SAFETY RECALL BEGAN ON JULY 28, 2009. OWNERS MAY CONTACT DOPE, INC. AT 1-626-272-1798.
EXTERIOR LIGHTING · 09E012000
2009-04-07
SABERSPORT IS RECALLING 16,270 COMBINATION CORNER AND BUMPER LAMP ASSEMBLIES OF VARIOUS PART NUMBERS SOLD FOR USE AS AFTERMARKET EQUIPMENT FOR VARIOUS PASSENGER VEHICLES. THESE HEADLAMPS FAIL TO CONFORM TO THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 108, "LAMPS, REFLECTIVE DEVICES, AND ASSOCIATED EQUIPMENT." THESE LAMPS DO NOT CONTAIN THE REQUIRED AMBER SIDE REFLECTORS.
Consequence: DECREASED LIGHTING VISIBILITY MAY RESULT IN A VEHICLE CRASH.
Remedy: SABERSPORT WILL NOTIFY OWNERS AND OFFER A FULL REFUND FOR THE NONCOMPLIANT COMBINATION LAMPS. THE SAFETY RECALL BEGAN ON MAY 11, 2009. OWNERS MAY CONTACT SABERSPORT AT 1-909-598-7589.
VEHICLE SPEED CONTROL:CRUISE CONTROL · 07E005000
2007-01-18
CERTAIN ROSTRA CRUISE CONTROLS, P/NOS. 00012-X0486-01, 00015-X0486-01, 00012-X0486-21, 00016-79910, 00016-79910-01, AND 250-1755, INSTALLED AS ORIGINAL EQUIPMENT ON MY 2006-2007 GULF STATES TOYOTA AND SOUTHEAST TOYOTA SCION VEHICLES AND ALSO SOLD AS AFTERMARKET EQUIPMENT. THE CRUISE CONTROL MAY NOT RETURN TO IDLE WHEN THE ON/OFF SWITCH IS PRESSED FOR THE FIRST TIME.
Consequence: FAILURE TO RELEASE THE THROTTLE WHEN THE CRUISE CONTROL IS TURNED OFF COULD RESULT IN A VEHICLE CRASH.
Remedy: THE VEHICLE MANUFACTURERS WILL NOTIFY THEIR OWNERS AND REPLACE THE CRUISE CONTROL FREE OF CHARGE. ROSTRA WILL NOTIFY PURCHASERS OF THE ATERMARKET CRUISE CONTROLS AND REPLACE THE UNITS FREE OF CHARGE. THE RECALL BEGAN ON FEBRUARY 13, 2007. OWNERS CAN CONTACT ROSTRA AT 910-291-2538.
EXTERIOR LIGHTING · 06E064000
2006-07-17
CERTAIN TRADESONIC COMBINATION LAMPS SOLD AS REPLACEMENT LAMPS FOR USE ON THE ABOVE LISTED PASSENGER VEHICLES. COMBINATION LAMPS NOT EQUIPPED WITH AMBER SIDE REFLECTORS FAIL TO CONFORM WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 108, LAMPS, REFLECTIVE DEVICES, AND ASSOCIATED EQUIPMENT.
Consequence: LACK OF AMBER SIDE REFLECTORS IN THE LAMPS WILL DECREASE LIGHTING VISIBILITY TO OTHER DRIVERS AND MAY POSSIBLY RESULT IN A VEHICLE CRASH.
Remedy: TRADESONIC WILL NOTIFY OWNERS AND REPLACE THE LAMPS FREE OF CHARGE. THE RECALL IS EXPECTED TO BEGIN DURING JULY 2006. OWNERS MAY CONTACT TRADESONIC AT 626-934-8884.
EXTERIOR LIGHTING · 06E060000
2006-06-29
CERTAIN AAI MOTORSPORTS COMBINATION LAMPS SOLD AS REPLACEMENT LAMPS FOR USE ON THE ABOVE LIST PASSENGER VEHICLES. COMBINATION LAMPS NOT EQUIPPED WITH AMBER SIDE REFLECTORS FAIL TO CONFORM WITH THE REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 108, "LAMPS, REFLECTIVE DEVICES, AND ASSOCIATED EQUIPMENT."
Consequence: LACK OF AMBER SIDE REFLECTORS IN THE LAMPS WILL DECREASE LIGHTING VISIBILITY TO OTHER DRIVERS AND MAY POSSIBLY RESULT IN A VEHICLE CRASH
Remedy: AAI MOTORSPORTS WILL NOTIFY OWNERS AND REPLACE THE LAMPS FREE OF CHARGE. THE RECALL BEGAN ON AUGUST 1, 2006. OWNERS MAY CONTACT AAI MOTORSPORTS AT 909-923-9188.
EXTERIOR LIGHTING:HEADLIGHTS · 06E023000
2006-03-13
CERTAIN ANZO COMBINATION HEADLAMP ASSEMBLIES SOLD AS REPLACEMENT LAMPS FOR USE ON CERTAIN PASSENGER VEHICLES. SOME COMBINATION LAMPS ARE NOT EQUIPPED WITH AMBER SIDE REFLECTORS WHICH FAIL TO CONFORM TO FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 108, "LAMPS, REFLECTIVE DEVICES, AND ASSOCIATED EQUIPMENT."
Consequence: WITHOUT THE AMBER REFLECTORS, THE VEHICLE WILL BE POORLY ILLUMINATED, POSSIBLY RESULTING IN A VEHICLE CRASH.
Remedy: ANZO WILL NOTIFY OWNERS AND REPLACE THE HEADLAMPS FREE OF CHARGE. THE RECALL BEGAN MAY 9, 2006. OWNERS MAY CONTACT ANZO USA AT 909-468-3688.
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