3 days before Christmas whilst accelerating onto the M4 I had the ‘Injection Fault – STOP’ message flash up for a few seconds. It never did it again on that journey but the next day it happened again, multiple times. There wasn’t anything wrong with the car running; no noises or smoke or lack of power just the occasional ‘Injection Fault’ message only when trying to accelerate from say 30 to 50 or 50 to 70 and the message clears the moment you ease off the gas. It was still possible to drive at a constant 70mph without any noticeable problems.
The next day, trying to start it was difficult. The car would normally fire on the first turn of the starter but instead the dreaded ‘Injection Fault – STOP’ appears and 10 or more presses of the start button were necessary before the engine fired up. When it did start though, again there is nothing to make you suspect that anything is wrong, it drives and responds perfectly normally, aside from the Injection Fault when accelerating hard.
Having read the online Renault forums it seems that this fault, exactly how I’m describing it happens to lots of people with the same car/engine. Sadly there doesn’t seem to be any consensus as to the specific cause. Perhaps this is because it could be a few different things but with the description of the symptoms and the circumstances being so exact, I find it hard to believe it’s not the very same problem each time.
One thing people seemed to recommend before anything drastic was to replace the Diesel Filter. Not the easiest job on a Scenic but with some added swearing, this was just about within my range. I bought a new filter from EuroCarParts, half the price of the Renault original.
Changing the filter didn’t fix the problem and starting the car was getting progressively harder and I started needing another car to jump it off but eventually it would start without even a cough and just drive normally – but with the ‘Injection Fault - STOP’ coming up on any hills or acceleration.
So I gave in and Googled ‘Diesel Specialists’ in the Oxford area, near to my work and found a firm who were ‘Delphi’ specialists and so they seemed ideal. I booked it in and got the Scenic to them. They called me a few hours later to say it was a ‘Diesel Pressure’ problem. “It was 80 bar at cranking when it should be over 200”. They suspected it was one or more Injectors but couldn’t do a leak off test because the hand primer’s non-return valve was broken and until that was fixed it was impossible to do a conclusive leak-off test.
I knew the Hand Primer was useless as I struggled to prime the system after replacing the filter weeks earlier. I asked them to put a new hand-primer in place which they did and then reported back to me the result of the leak-off test.
The result being that injectors 1 and 4 were leaking back quite badly.
But their recommendation was to take all 4 injectors AND the High Pressure pump off and send them off to a firm in Colchester, who would test each component and then if necessary restore or replace them with reconditioned ones. The rough total for all of this would be around a grand!
The car is only worth £1500 or it would be if it worked. I had hoped that as these Diesel Specialists had a nice ‘Delphi’ sign above their door, THEY were the people who would test and recon anything that needed doing but I think this firm wasn’t as specialist as I’d imagined.
When I said the car isn’t worth spending a grand on, they said they could perhaps just replace the two injectors with two recon ones from the firm in Colchester, which happen to have my exact ones on the shelf. £160 each plus VAT. BUT with the caveat that as the problem 'could' be caused by contamination from a shredding fuel pump, they couldn’t guarantee how long it would last, it might be 6 weeks, 6 months or 6 years, as long as I was willing to risk it with no come backs on them.
I agreed and they did it and phoned to say it starts perfectly, first time, as it always had, everything was back to normal. Hurrah!
With the new hand-primer fitted, the diagnostics/leak-off and the Injectors removal refitting/coded, the total bill was £580. In my dreams I’d hoped for £300. Set myself a limit of £500. £580 was painful but it was fixed so I paid it and crossed my fingers.
8 Days. It lasted 8 days.
Started with a two button press to start with the ‘Injection Fault – coming up. Next day, it took 9 goes to start, the following day 15 presses and now it’s again only ‘Easy Start’ or jumping from another running car that will do it - eventually.
I never did check the old diesel filter when I changed it at Christmas so this week, with the problem back I decided to have a look. Being the 1.5, this is the Sealed Unit filter so I had to hack-saw it open to examine the filter for any signs of the dreaded shredded fuel pump. Aside from an oily old filter, which was probably the 2005 original, there was no sign of any shiny metal or dirty filings or anything else.
I haven’t been back to or even phoned the Delphi garage with the bad news for me - good news for them.
I might find another garage though, perhaps a specialist who recons the injectors and/or pumps on site and has a drawer full of old spares to try things out and see if it works before spending my money unnecessarily.
So in summary, it has a new fuel filter (fitted by me) the old filter shows no sign of nasty metal bits
And now two reconditioned Injectors 1 and 4 with the car running perfectly for 8 days, then with the same progression of the fault from occasional Injection Fault warning on day one, to it being harder and harder - near impossible to start.
Today, I fitted 4 new Glow Plugs as I found one was open circuit. I know it probably pointless (it was) but I felt I was doing something to help.
Before I call another garage, is there anything else I could/should try?
Sorry for the essay, this is so depressing and writing all down is probably therapy
