Spanner light
On my 2001 Vectra, the EML light (car with a spanner through the roof) comes on when the ignition is first turned, then goes out when the engine is started and will stay off till I give it a bit of welly, after which the light comes on again. The light will then stay on until the car is restarted, when it will go out and not come on at all till I give it another bit of welly. Recently, there was an occasion when the engine ran very roughly for three to four minutes with the EML light on. The problem cleared itself, but the code left was for 'No 3-cylinder rough running'.
I think the two problems are related – possibly the injectors are partly blocked. Petrol used is Shell Ultra, which is supposed to clean the injectors/inlets. My code reader is an Autel MS409 from around 2010. Am I correct in my diagnosis of the problem or is there something I have missed? I have changed both Lambda sensors (both appeared to be originals) as well as the MAF sensor. The rear Lambda sensor failed about two months after it was fitted – it was changed by Autovaux, who said there had been a few failures of these Delphi sensors.
My local Vauxhall dealer said to not worry about the problem as the car still drives OK, but I would appreciate your views on this subject. Nigel Bird
You do not mention the engine size of your Vectra, but as you are using Shell petrol and given the year, I am assuming it is either a 1.6 or 2.2.
The EML should illuminate when the ignition is turned on and extinguish when the engine is started. You do not mention the code obtained and this may help narrow down the problem. The cause of the code showing No 3 cylinder running rough is as likely to be an ignition fault as an injection problem.
If the spark plugs have not been changed recently, this should be your first move. I would also check the wiring to the coil pack assembly and ensure the plug is clean and dry. In case the problem is injector-related, you should also check the integrity of the injector electrical connections. The problem may also be with the coil pack unit and if no other faults can be found it may be worth considering replacing this.