Change Injectors

[qman3428]

I have tried the search function but it is not returning any results no matter what I put in!

 

If I accelerate hard I leave a cloud of black smoke behind me and believe it may be a faulty injector, my question is, because it is a common rail system, how do I vent the pressure before removing the injectors for inspection.

the car is a 2.0 hdi C5 exclusive on 2009 plate

[pdjones]

Do you know that diesel injected under the skin can kill you? That's why only specialists should touch these motors. Be careful.

[Parkesie]

Black smoke when accelerating hard is more likely to be a restricted air filter or a boost leak I'd check the condition of the air intake pipes the air cooler and filter housing before pulling injectors.

[coastline taxis]

Take the car and thrash the arse of it down the motorway. its still a fairley new car and your probally nursing it round the town get it up to 60ish in 3rd and watch all the black soot come out the back. Itl also work the egr valve a bit and the car will run better. Diesels are filthy engines and need to be worked hard to get the best out of them.  in the trade its called a italian tune up

[qman3428]

Yes I am aware of the risks of oil under pressure, hence why I asked the question in the first place but thanks for the heads up.

 

The air filter is a K&N panel filter and was cleaned and re-oiled two weeks ago, I checked it last weekend to see if it was over oiled and it is fine. The air intake is lined with a black gunge but I wiped a lot of it out and short of it going through the valves in dollops I dont see that being the issue and I have been experiencing this fault for a few months.

 

The EGR valve is new and I do 550 motorway miles every week and yes I do knock hell out of it (regular over 3000 rpm). It went through the MOT a month ago with no faults or advisories but if I set off at speed I do leave a black cloud behind me (great for those cyclists who cut me up in London). There is a knock (like a tappet) at tick over and the idle is a litle rough. My thought is that an injector is supplying a jet instead of a spray, hence the above faults. I wanted to take them out and see if there was obvious crud on the injectors. It is in the main dealers next week for a cam belt replacement (100,000 miles) and I will ask them to diagnose the noise. I will report back then.

 

It would be nice to know how to depresurise the system, just in case I do need a new injector. Though I have been told they get stuck in the head.

 

Thanks for the replies.

[coastline taxis]

To depresurize the system.

 

Take key out of ignition

Wait 5 mins for ecu to go to sleep

 

Job done

[qman3428]

Thanks Coastline, I thought there would be a release valve or something, nice to know it is so simple.