Replace valve stem seals to address oil consumption or blue exhaust smoke by removing the cylinder head camshafts and using compressed air to hold valves in place during seal replacement.

Warnings

Tools required

Parts

• Valve stem seal set (16 seals - intake and exhaust) × 1 — Use OEM Toyota specification
• Valve cover gasket × 1 — Use OEM specification
• Valve cover grommets/seals × 1 — Use OEM specification
• Camshaft position sensor O-ring × 1 — Use OEM specification
• Spark plug tube seals × 4 — Use OEM specification
• Engine oil × 1 — Toyota Genuine 0W-20
• Engine coolant (if draining) × 1 — Toyota Super Long Life Coolant Pink

Fluids

• Toyota Genuine 0W-20 — 4.5 qt
• Toyota Super Long Life Coolant (Pink) — 2 qt

Preparation

1. Ensure engine is completely cold before starting work
2. Disconnect negative battery cable and secure away from terminal
3. Remove engine cover and plastic shields from top of engine
4. Drain engine coolant if coolant hoses interfere with valve cover access
5. Remove air intake tube and air filter housing assembly
6. Disconnect all electrical connectors from valve cover area (ignition coils, sensors)
7. Label and photograph all vacuum hoses and wiring for proper reinstallation
8. Remove ignition coils from all four cylinders
9. Place clean shop towels in engine bay to catch dropped parts
10. Have a parts organizer ready to keep valve keepers, springs, and retainers separated by cylinder

Procedure

1. 1

   Remove spark plugs and prepare cylinders
   Remove all four spark plugs using a 16mm spark plug socket. Inspect plug condition and note any oil fouling which confirms seal failure. Keep plugs in order by cylinder for diagnostic reference. Clean any debris from spark plug wells before proceeding.
2. 2

   Remove valve cover assembly
   Remove all PCV hoses and breather connections from valve cover. Remove valve cover bolts in reverse of tightening sequence (outside to inside pattern). Carefully lift valve cover away, tapping gently with plastic mallet if stuck. Do not pry against sealing surfaces. Clean any oil residue from cylinder head deck surface.
3. 3

   Set engine to TDC for cylinder 1
   Rotate crankshaft clockwise using 19mm socket on crankshaft pulley bolt until cylinder 1 is at top dead center on compression stroke. Verify timing marks on camshaft gears align with marks on timing chain cover. Both intake and exhaust cam lobes for cylinder 1 should point away from valve lifters. This is critical for timing reference.
4. 4

   Mark and remove camshaft caps
   Using a permanent marker or paint pen, mark each camshaft cap with its position number and orientation arrow pointing toward front of engine. The 2ZR-FE engine has numbered caps - verify markings are clearly visible. Loosen camshaft cap bolts in reverse sequence (outside caps first, center caps last) in multiple passes to gradually release spring tension. Remove bolts and caps, keeping them in exact order. Note that some caps have oil passages that must align during reinstallation.
5. 5

   Remove camshafts and inspect
   Carefully lift both intake and exhaust camshafts straight up from cylinder head, keeping them identified (intake has VVT actuator). Place camshafts on clean padded surface where they cannot roll. Inspect camshaft journals and lobes for scoring or wear. Inspect cam followers (direct-acting type on this engine) for wear on contact surfaces. Leave cam followers in place in cylinder head.
6. 6

   Install compressed air adapter on cylinder 1
   Thread compressed air adapter fitting into cylinder 1 spark plug hole. Connect air line and pressurize cylinder to approximately 90-100 PSI. Listen for air leaks past rings (normal slight leakage at oil fill or dipstick). The air pressure will hold both valves seated against their seats. If cylinder will not hold pressure, bring piston down slightly from TDC and try again, or this method will not work and cylinder head removal is required.
7. 7

   Compress valve springs and remove keepers for cylinder 1
   Using overhead cam valve spring compressor, carefully compress the first valve spring just enough to release tension on the valve keepers (collets). Use magnetic pickup tool or small pliers to remove both keepers from valve stem groove. Place keepers immediately in labeled container. Release spring compressor slowly and remove spring retainer and spring. Repeat for second valve on cylinder 1 (both intake and exhaust). Work carefully as compressed air will prevent valve from dropping but spring pressure is significant.
8. 8

   Remove old valve seals from cylinder 1
   Using valve seal pliers or careful prying with hooked tool, remove old valve stem seal from top of valve guide. The seal is a tight press fit. Inspect valve guide for carbon buildup or damage. Clean valve stem and guide area with clean solvent and lint-free cloth. Check valve stem for scoring or wear. Repeat for both valves on cylinder 1.
9. 9

   Install new valve seals on cylinder 1
   Lightly oil new valve seal O.D. with clean engine oil. Using valve seal installation tool (correctly sized plastic sleeve), carefully press new seal straight down over valve stem and onto valve guide until it seats against cylinder head. The seal should bottom out with firm resistance - do not over-press and damage seal. Ensure seal lips face down toward combustion chamber. Install protective plastic sleeve over valve keeper groove to prevent seal damage during spring installation. Repeat for both valves on cylinder 1.
10. 10

    Reassemble valve train for cylinder 1
    Install valve spring and retainer over valve stem and protective sleeve. Compress spring with spring compressor tool. Remove protective sleeve and carefully install both valve keepers into stem groove using magnetic tool or small screwdriver. Release spring compressor gradually while ensuring keepers seat properly in groove. Tap valve stem tip lightly with plastic tool to verify keepers are locked in place. Repeat for second valve on cylinder 1. Remove compressed air adapter.
11. 11

    Repeat seal replacement for cylinders 2, 3, and 4
    Rotate crankshaft to bring next cylinder to TDC on compression stroke (firing order is 1-3-4-2, so rotate 180 degrees for cylinder 3, then 180 for cylinder 4, then 180 for cylinder 2). For each cylinder: install air adapter, pressurize, compress springs, remove keepers, remove springs, replace seals, reinstall springs and keepers, remove air. Work methodically and avoid rushing. Each cylinder should take 30-45 minutes. Verify keepers are properly seated on each valve before moving to next cylinder.
12. 12

    Clean and prepare for camshaft installation
    With all valve seals replaced, thoroughly clean all camshaft journals in cylinder head using clean lint-free cloth and solvent. Clean camshaft bearing surfaces on camshafts. Inspect all cam followers to ensure they move freely in their bores. Apply clean engine oil to all camshaft journals in cylinder head, all cam lobes, and all cam follower contact surfaces.
13. 13

    Install camshafts with timing alignment
    Rotate crankshaft to TDC position for cylinder 1 (timing marks aligned). Apply engine assembly lube or fresh 0W-20 oil to all journal surfaces. Carefully lower both camshafts into position with timing marks on cam gears aligned to marks on timing chain cover. The intake cam (with VVT actuator) goes on intake side, exhaust cam on exhaust side. Ensure cam lobes for cylinder 1 point away from followers. Verify timing chain engagement on both cam gears has not shifted.
14. 14

    Install camshaft caps in sequence
    Apply light coat of clean engine oil to camshaft cap journal surfaces. Install all camshaft caps in their original positions according to your markings, with orientation arrows pointing toward front of engine. Hand-start all cap bolts. Tighten camshaft cap bolts in sequence from center caps outward to outer caps, in multiple passes (3-4 passes recommended). First pass: 5 Nm, second pass: 10 Nm, final pass: 14 Nm. This gradual tightening prevents camshaft distortion. Ensure camshafts rotate freely by hand after installation.
    Torque spec

    Camshaft Cap Bolts14 Nm (10 lb-ft)
15. 15

    Install valve cover with new gasket
    Install new valve cover gasket into valve cover groove ensuring proper seating all around. Install new spark plug tube seals and any grommets. Clean valve cover mating surface on cylinder head with plastic scraper and solvent. Apply small dab of RTV sealant at front corners where timing chain cover meets cylinder head (two locations only). Position valve cover carefully and install bolts finger tight. Tighten valve cover bolts in sequence from center outward to 10 Nm. Reconnect PCV hoses and breather tubes.
    Torque spec

    Cover Bolts15 Nm (11 lb-ft)
16. 16

    Install spark plugs and ignition components
    Apply small amount of anti-seize compound to spark plug threads (avoid electrode area). Install all four spark plugs and tighten to specified torque. Reinstall ignition coils into spark plug wells and secure with mounting bolts. Reconnect all ignition coil electrical connectors. Ensure all connectors click firmly into place.
    Torque spec

    Spark Plugs - Aluminum Head20 Nm (15 lb-ft)

Reassembly

1. Reinstall air intake system and secure all clamps
2. Reconnect all vacuum hoses according to photos taken during disassembly
3. Refill cooling system if coolant was drained during preparation
4. Reconnect battery negative cable
5. Fill engine with fresh 0W-20 oil to proper level on dipstick

Verification

• Before starting engine, manually rotate crankshaft two full revolutions by hand to verify no interference and proper valve operation
• Verify timing marks return to TDC alignment after two revolutions
• Start engine and listen for abnormal valve train noise - should be quiet with proper oil pressure
• Check for oil leaks around valve cover gasket after engine reaches operating temperature
• Allow engine to idle for 10 minutes and monitor for smooth operation
• After 50-100 miles of driving, check oil consumption - should be significantly reduced or eliminated
• Monitor exhaust for blue smoke on deceleration or startup - should be eliminated if seals were the issue
• Recheck valve cover bolt torque after first heat cycle (engine cool down)

More procedures for this vehicle