Common problems

Applies to: ZZE121R, ZZE122R (PK); JDM ZZE12#

You notice: Oil level drops between changes, blue smoke, oil-fouled plugs and misfire

Usual cause: Piston oil-control rings and oil-return holes clog or stick. Toyota revised the rings around 2005. Worn valve stem seals at high km.

Fix: Measure consumption (above ~1 L/1,000 km is excessive). Fix with new rings and pistons (updated), valve stem seals or a short block.

Codes: P0300P0304

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Applies to: All petrol E120

You notice: Rough idle, jerking at ~100 km/h, flashing CEL, poor fuel average

Usual cause: Coils age with heat; cheap non-OEM coils re-fail; oil in plug tubes from a leaking valve-cover / tube seal; broken IGF wire

Fix: Swap coils to confirm; fit OEM/Denso coils; replace plugs; fix tube-seal oil leaks; check the IGF circuit

Codes: P0300P0304P0351P0354P1300P1305P1310P1315

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Applies to: ZZE122R / 1ZZ-FE (US-sister evidence)

You notice: Lean code, rough cold idle, misfire

Usual cause: The original black rubber gasket hardens; Toyota TSB EG045-07 gives the updated (orange) gasket 17171-22060

Fix: Smoke-test and replace the gasket

Codes: P0171P0300

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Applies to: All E120 (MAF on NZ and ZZ per RM821E)

You notice: Lack of power, lean code, poor average

Usual cause: Dirt/oil on the hot wire (esp. oiled filters)

Fix: Clean with MAF cleaner; replace if out of spec

Codes: P0100P0171

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Applies to: NZE120R (2NZ) and ZZ engines with IACV

You notice: RPM dips to ~400 or the engine stalls when the clutch is pressed or the A/C comes on

Usual cause: Carbon in the throttle body / rotary IAC valve

Fix: Clean the throttle body and IACV; check vacuum leaks; normal idle 750-850 rpm (forum)

Codes: P0505

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Applies to: All E120

You notice: Poor fuel average, CEL

Usual cause: O2 sensor wears (~100k miles)

Fix: Test or replace the sensor

Codes: P0130P0133P0135

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Applies to: 1ZZ (US-sister); PK 2NZ/3ZZ unverified

You notice: Squeal or rattle from the belt area

Usual cause: Stretched OEM belt plus leaking tensioner damper

Fix: Replace the belt and tensioner with OEM

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Applies to: 1ZZ-FE/2ZZ

You notice: Oil on the rear of the engine, little dripping

Usual cause: Hardened tensioner O-ring

Fix: Replace the O-ring / tensioner

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Applies to: All petrol

You notice: Oil smell, oil in plug wells causing misfire

Usual cause: Aged gasket

Fix: Replace the gasket and tube seals (OEM)

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Applies to: 1ZZ-FE; others likely

You notice: Coolant loss, puddles, squeal, overheating

Usual cause: Seal wear from ~100,000 km

Fix: Paper-towel test: replace only if actively wet (Toyota diagnostic tip)

Codes: P0115P0116

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Applies to: All; PK 1.3 thread

You notice: Temperature rises on long runs or with A/C

Usual cause: Fan fuse/relay/motor, stuck thermostat, blocked radiator, air pockets

Fix: Check the RDI FAN 40 A fuse and fan relay, ECT sensor, thermostat; flush the radiator; bleed

Codes: P0115P0116

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Applies to: PK cars (hydraulic PS)

You notice: Fluid leaks at the rack and pump, whine on turning, heavy or jerky steering

Usual cause: Worn rack seals; pump damaged by running low; air drawn in at return-line clamps; wrong fluid

Fix: Use ATF only; fix clamps; replace the pump and flush 3-4 L ATF; rebuild or replace the rack

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Applies to: All E120

You notice: Clunk or creak over speed breakers

Usual cause: Worn lower-arm bushes, stabiliser links, tie-rod ends

Fix: Inspect and replace the bushes, links and rack ends

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Applies to: All

You notice: Speed-dependent hum

Usual cause: Worn bearing

Fix: Replace the bearing

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Applies to: ZZE121R-GEPNKP (PK 1.6 auto)

You notice: 2-3 flare or bind-up, slipping in 3rd/4th, stalls at a stop

Usual cause: Worn valve body, solenoids, degraded ATF; ECM logic on some years

Fix: Check ATF (Toyota T-IV); test solenoids; valve-body kit; scan codes

Codes: P0741P0750P0770P0773

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Applies to: US ZZE130 sister; PK ZZE122R unverified

You notice: Harsh shift, CEL

Usual cause: ECM fault (US recall 10V384 / TSB TC015-07)

Fix: Check the VIN for a campaign (US/Gulf). PK applicability unverified.

Codes: P2716

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Applies to: ZZE122R-GEPNKP

You notice: Delay into D/R

Usual cause: Low or burnt ATF, solenoid

Fix: Check ATF level and condition, scan, pressure test

Codes: P0750P0770

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Applies to: PK (forum)

You notice: Weak cooling, compressor cycling, RPM surge after a non-OEM swap

Usual cause: Compressor/clutch wear, overcharge (gas not weighed), clogged condenser

Fix: Weigh the charge; PAG46 oil; matching Denso clutch compressor; wash the condenser. Avoid Honda swaps (RPM surge).

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Applies to: All E120 (US recall evidence)

You notice: Windows don't work from the driver switch

Usual cause: Worn switch contacts / sticky switch (US recalls 08V162 MY2003-04 and 12V491 MY2007-09)

Fix: Clean/lube or replace the master switch; test motor and ground

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Applies to: All petrol

You notice: Ping on throttle in high gear

Usual cause: Low-octane fuel, carbon, knock sensor

Fix: Use the correct RON (91 NZ/1ZZ, 95 3ZZ per toyota-club); decarbonise; check the sensor

Codes: P0325

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Applies to: US/Gulf E120; PK VIN check

You notice: None until deployment (rupture risk)

Usual cause: Moisture-degraded PSAN inflator

Fix: VIN check and inflator replacement

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Applies to: ZZE121R 1.6 AT (forum)

You notice: 5-6 km/L

Usual cause: Non-OEM coils, dirty MAF/throttle, wrong AFR

Fix: OEM coils and plugs, clean MAF/throttle body, check the O2 sensor

Codes: P0171P0172

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