Lexus ES: Rear valve cover gasket leak and steady oil consumption
Rear valve cover gasket leak and steady oil consumption is a common fluid leaks fault on the Lexus ES on the 1996–2003 cars, and we rate it major. Putting it right costs $500 to $1,500 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 12 documented faults on the Lexus ES.
- Vehicle
- Lexus ES
- Engine
- 3.0L
- Years
- 1996–2003
- Fuel
- petrol
- System
- Fluid Leaks
What you are looking at
No photograph available
What goes wrong
Two related ageing traits on the 1MZ-FE. The rear valve cover gasket — on the bank tucked against the bulkhead — hardens and leaks, and because it is awkward to reach it is a job people put off, so the oil drips onto the exhaust below and produces a burning smell and occasional smoke from the engine bay. Separately, these engines burn oil as the piston rings and valve stem seals age, which matters more than usual here because low oil is exactly what brings on the sludge problem. So the useful question at the viewing is not just "does it leak" but "how often do you top it up", and whether the owner actually checks.
What you would notice
- Burning-oil smell after driving, strongest when you open the bonnet
- Wisps of smoke from the back of the engine bay at idle
- Oil level down between services with no puddle on the ground
- Blue smoke on start-up after standing
How to check it
Where to look. Rear valve cover, on the cylinder bank against the bulkhead at the back of the engine
Open the bonnet after the test drive rather than before, and smell for hot oil.
Shine a torch down the back of the engine, between the rear cylinder head and the bulkhead, looking for wet oil or a baked black crust on the exhaust below.
Check the dipstick level before the car is started and ask the owner how much oil it uses and how often they check it — an owner who does not check is the bigger finding on this engine.
Watch the mirror for a puff of blue smoke on a hard pull.
If a workshop inspection is possible: ask for the source of any leak to be identified in writing, since a rear cover gasket and a rear main seal look the same from above and cost very differently.
What it costs to put right
$500 to $1,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.
Ask the seller
- “How much oil does it use between services?”
- “Has either valve cover gasket been replaced?”
- “Do you check the oil, and how often?”
Now check the Lexus ES you are actually looking at
Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.
Where this comes from
- CarSpec (Minnesota) — 'Toyota and Lexus 3.0 V6 (1MZ) burning oil: diagnostic tips and repair'
- Bob Is The Oil Guy forums — '1996 Lexus ES300 1MZ-FE oil leak' thread
Lexus ES buyer questions
Is rear valve cover gasket leak and steady oil consumption serious on a Lexus ES?
We rate it major and common on the Lexus ES. Two related ageing traits on the 1MZ-FE. The rear valve cover gasket — on the bank tucked against the bulkhead — hardens and leaks, and because it is awkward to reach it is a job people put off, so the oil drips onto the exhaust below and produces a burning smell and occasional smoke from the engine bay. Separately, these engines burn oil as the piston rings and valve stem seals age, which matters more than usual here because low oil is exactly what brings on the sludge problem. So the useful question at the viewing is not just "does it leak" but "how often do you top it up", and whether the owner actually checks.
How much does it cost to fix on a Lexus ES?
$500 to $1,500 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.
Which Lexus ES years are affected?
Our research records this fault on the 1996–2003 Lexus ES. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.
How do I check for it before I buy?
Open the bonnet after the test drive rather than before, and smell for hot oil. Shine a torch down the back of the engine, between the rear cylinder head and the bulkhead, looking for wet oil or a baked black crust on the exhaust below. Check the dipstick level before the car is started and ask the owner how much oil it uses and how often they check it — an owner who does not check is the bigger finding on this engine. Watch the mirror for a puff of blue smoke on a hard pull. If a workshop inspection is possible: ask for the source of any leak to be identified in writing, since a rear cover gasket and a rear main seal look the same from above and cost very differently. Look here: Rear valve cover, on the cylinder bank against the bulkhead at the back of the engine