Toyota Prado: Lower intake manifold gasket and bypass pipe coolant leak (3.4 V6 5VZ-FE)
Lower intake manifold gasket and bypass pipe coolant leak (3.4 V6 5VZ-FE) is a common cooling fault on the Toyota Prado on the 1996–2002 cars, and we rate it major. Putting it right costs $600 to $1,400 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 64 documented faults on the Toyota Prado.
- Vehicle
- Toyota Prado
- Engine
- 5VZ-FE
- Years
- 1996–2002
- Fuel
- petrol
- System
- Cooling
What you are looking at
No photograph available
What goes wrong
The 3.4 petrol V6 runs coolant through the lower intake manifold and a metal bypass pipe under the intake, in the valley between the cylinder banks. With age the lower intake gaskets and the bypass pipe seals seep, showing up as slow coolant loss and a leak that seems to come from the back of the engine or pools out of sight in the valley. It is one of the best-documented jobs on this engine worldwide: the parts are cheap but reaching them means the intake comes off. Ignored long enough on an alloy-head V6, it becomes overheating and head work.
What you would notice
- Coolant level dropping with no puddle underneath
- Coolant smell after a drive, strongest at the back of the engine
- Dried pink or green coolant crust around the intake manifold
- Temperature creeping on long climbs as the level falls
How to check it
Where to look. Centre of the engine — under and behind the intake manifold, in the engine valley
Check the coolant reservoir level and ask how often it needs topping up — slow loss with no visible puddle is the classic sign. With the engine warm, smell the engine bay for coolant, and use a phone torch to look for dried coolant crust around and behind the intake manifold in the centre of the engine. Watch the temperature gauge on the test drive, especially on a long climb. If a workshop inspection is possible: a cooling-system pressure test shows the seep, and with the intake off the valley and bypass pipe can be inspected — the pipe's seals should be replaced in the same job as the gaskets.
What it costs to put right
$600 to $1,400 at New Zealand independent workshop rates. That is for this job on its own, not for the car.
Ask the seller
- “How often does the coolant need topping up?”
- “Has the intake ever been off to reseal the gaskets or bypass pipe?”
- “Any overheating history?”
Now check the Toyota Prado 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
- Toyota 4Runner forum (toyota-4runner.org) — 'Lower intake manifold gasket replacement' and 'Leaking coolant from the back of the engine — 3.4L V6 5VZ-FE' threads
- The 4Runner Files — 5VZ-FE intake manifold gasket replacement and rear coolant leak write-up
- Tacoma World — '5VZ-FE slow coolant loss' thread
- Prado South Africa owners group — coolant loss reports on the 3.4 petrol 90-series
Toyota Prado buyer questions
Is lower intake manifold gasket and bypass pipe coolant leak (3.4 v6 5vz-fe) serious on a Toyota Prado?
We rate it major and common on the Toyota Prado. The 3.4 petrol V6 runs coolant through the lower intake manifold and a metal bypass pipe under the intake, in the valley between the cylinder banks. With age the lower intake gaskets and the bypass pipe seals seep, showing up as slow coolant loss and a leak that seems to come from the back of the engine or pools out of sight in the valley. It is one of the best-documented jobs on this engine worldwide: the parts are cheap but reaching them means the intake comes off. Ignored long enough on an alloy-head V6, it becomes overheating and head work.
How much does it cost to fix on a Toyota Prado?
$600 to $1,400 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 Toyota Prado years are affected?
Our research records this fault on the 1996–2002 Toyota Prado. 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?
Check the coolant reservoir level and ask how often it needs topping up — slow loss with no visible puddle is the classic sign. With the engine warm, smell the engine bay for coolant, and use a phone torch to look for dried coolant crust around and behind the intake manifold in the centre of the engine. Watch the temperature gauge on the test drive, especially on a long climb. If a workshop inspection is possible: a cooling-system pressure test shows the seep, and with the intake off the valley and bypass pipe can be inspected — the pipe's seals should be replaced in the same job as the gaskets. Look here: Centre of the engine — under and behind the intake manifold, in the engine valley