Either you have a real and valid injection fault - in which case you should take it to a garage for diagnosis and repair - or - you have a false report of an injection fault in which case you should take it to a garage for diagnosis and repair.
The injection fault warning very probably comes from the software programme in the engine management computer - but it may also be a fault with the dashboard - there are several reports on here of dashboards on Meganes & Scenics failing but as far as I recall they do not mention the symptom that you have.
Use the search feature - top right.
Somebody posted this....
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Hi, I know the "Check Injection" error message is old message, march 2009. My wife had the same one yesterday, I went and had a look, had to buy a Haynes manual first. Checked the "Diesel engine fuel and Exhaust systems" chapter.
Checked the general information, for the main componants. The fault finding chapter, engine misfires or idles unevenly.
Both parts point towards the air filter, (cheapest part of the system to eliminate £13.90). Changed this, found old one clogged, leaves, a fag butt. Vacumed the box out, new one in, problem gone.
The air filter clogged up lowers the air intake must lower the air flow, which is being monitored by the air flow monitor.
The same problem existed in my car, citreon picasso, again checked the manual and went for the cheapest option, air filter, lack of maintenance on my behalf as you do, try and fix it when it breaks.
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Good luck...
Peccavi, September 2010