Renault Scenic: K9K 1.5 dCi Injector Return Rail Banjo Bolt Washer Leak
K9K 1.5 dCi Injector Return Rail Banjo Bolt Washer Leak is a common fluid leaks fault on the Renault Scenic on the 2003–2016 cars, and we rate it major. Putting it right costs ≈A$170 to ≈A$510 at independent workshop rates, shown as an approximate guide in Australian dollars. 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 6 documented faults on the Renault Scenic.
- Vehicle
- Renault Scenic
- Engine
- 1.5L
- Years
- 2003–2016
- Fuel
- diesel
- System
- Fluid Leaks
What you are looking at
A common-rail diesel injector. Contamination damages the nozzle at the tip.
What goes wrong
The K9K 1.5 dCi common-rail diesel unit fitted to Scenic II and Scenic III uses the same injector fuel return rail banjo bolt sealing arrangement as other K9K applications. Copper or aluminium crush washers at the banjo fittings harden and lose elasticity through heat cycling, eventually cracking and allowing diesel fuel to leak from the low-pressure return circuit. Scenic family MPV driving patterns involving frequent short cold trips followed by sustained motorway runs create extreme thermal cycling stress on these washers and increase leak frequency relative to other K9K applications with more consistent driving profiles.
What you would notice
- Diesel fuel odour from engine compartment during and after driving
- Wet or oily residue around injector return rail banjo bolt fittings
- Smoke or steam visible from engine bay particularly after hot motorway driving
- Unexplained increase in fuel consumption
- Carbon staining on exhaust manifold adjacent to injector return area
How to check it
Where to look. Top of K9K engine cylinder head at injector return rail banjo bolt fittings, near the inlet manifold and turbocharger housing
With engine at operating temperature, inspect banjo bolt fittings on the injector fuel return rail for wet diesel seepage, discolouration or residue at the washer interface; examine exhaust manifold surface below the banjo fittings for black carbonised fuel deposits indicating historical or active leakage; review service history for evidence of banjo washer renewal or fuel system attention.
What it costs to put right
≈A$170 to ≈A$510 at independent workshop rates, shown as an approximate guide in Australian dollars. That is for this job on its own, not for the car.
Ask the seller
- “Have the injector return banjo bolt crush washers been replaced?”
- “Has any diesel smell been noticed from the engine bay?”
- “Has any fuel leak work been carried out on this vehicle?”
- “Is there any smoke or smell after extended motorway driving?”
Now check the Renault Scenic 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 still has money owing on it, has been written off or reported stolen, what kms it showed in past sale ads, whether it has had accident repair claims and what it is worth today. That comes from the official records for that plate. Enter the plate and its state for the A$17.90 Vehicle Check, or the full history from A$24.99.
Where this comes from
Renault Scenic buyer questions
Is k9k 1.5 dci injector return rail banjo bolt washer leak serious on a Renault Scenic?
We rate it major and common on the Renault Scenic. The K9K 1.5 dCi common-rail diesel unit fitted to Scenic II and Scenic III uses the same injector fuel return rail banjo bolt sealing arrangement as other K9K applications. Copper or aluminium crush washers at the banjo fittings harden and lose elasticity through heat cycling, eventually cracking and allowing diesel fuel to leak from the low-pressure return circuit. Scenic family MPV driving patterns involving frequent short cold trips followed by sustained motorway runs create extreme thermal cycling stress on these washers and increase leak frequency relative to other K9K applications with more consistent driving profiles.
How much does it cost to fix on a Renault Scenic?
≈A$170 to ≈A$510 at independent workshop rates, shown as an approximate guide in Australian dollars. 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 Renault Scenic years are affected?
Our research records this fault on the 2003–2016 Renault Scenic. 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?
With engine at operating temperature, inspect banjo bolt fittings on the injector fuel return rail for wet diesel seepage, discolouration or residue at the washer interface; examine exhaust manifold surface below the banjo fittings for black carbonised fuel deposits indicating historical or active leakage; review service history for evidence of banjo washer renewal or fuel system attention. Look here: Top of K9K engine cylinder head at injector return rail banjo bolt fittings, near the inlet manifold and turbocharger housing