TOPIC:

Hi fellow Kadjar owners,

Hope everyone is keeping safe and well in these difficult times.

I need some help/advice please.

I've a Renault Kadjar (66 Reg Dynamic S Nav) 1.5 dCi with 13500 miles on the clock. Due to ongoing Covid restrictions, the car has virtually sat on the drive since last service in September'20, only doing about 160 miles since then (these were couple of long drives on A roads/motorway rather than short trips around the town).

When I started the car few days ago, 'Check injection' message came up on the dashboard along with illuminated spanner (warning light). I drove around the backstreets for a bit (no more than a mile) before returning home as I didn't want to risk breaking down. The car itself had no problems starting up and it felt absolutely normal while driving, but I was on the backstreets doing no more than 20 miles/hour.

On starting the car again couple of days later, 'Check anti-pollution system' message came up on the dash along with 'Toxic Fume Filter System' warning light, with spanner light still illuminated.

Everything was clear in the last service. The car was on Renault A/B service regime and the last service was a B service (Oil and Filter change). Service staff at local Renault dealership had advised changing air and fuel filters, but I deferred until next service due to low mileage.

A google search tells me this issue is all too common with Renault cars and apparently all models can be affected – Kadjar/Capture/Clio/Megane/Grand Scenic to name a few. Frustratingly for me, the warranty expired in September.

Looking at Renault forums, I can see common culprits being :-
- Glow plugs
- Faulty oxygen sensor
- Blocked Diesel Particulate Filter (DPF) - Some people on forums recommend giving the car a good run on an A road/motorway to see if that clears up the DPF

I’m not very technical with cars, so wondering what the best course of action might be? All thoughts/suggestions/hints will be greatly appreciated!

My worry is taking it to a Renault dealership and being charged over the odds for a minor fault. So, if someone can recommend a good and reasonably priced independent Renault specialist in Essex/Kent – that would be great too.

Appreciate your help!

When Honest John in the Telegraph gets questions about DPF regeneration, his answer is generally along the lines of:

"It isn’t sustained road speed that regenerates the filter, but sustained engine speed.

I would try running the car at a sustained engine speed of 2,500-3,000rpm, probably in third or fourth gear. Hopefully that will sort out the problem."

I hope that helps.

Renault has a bit different approach for DPF regeneration than VAG or other manufacturers... system has 5th nozzle in exhaust mainfold before DPF and when temperature of exhaust gasses is high enough do a cyclic injection of petrol. Due to high temperature, self ignition of injected petrol occurs which reflect in fact that all captured parts in DPF burns... for that you do not need a constat high revs of engine either long enough driving. All you need is high enough temerature of exhaust gases. Regeneration can be done during slow, city driving.