Fuel Injector

[lewisg]

Hi,

We have a 2006 A Class Blue efficiency model. We've owned it for just over a year and before that we had the older model.

We went for another A Class due to the reliability we had form the older model.

Our new one has been fine and we've not had any problems whatsoever just like our last model - until now...

We had a engine management light come on which when plugged in flagged up 0% pressure in injector 3. The mechanic ran some additive through the tank and told us to run the diesel down then to come back if the light came back on.

It did come back on so we've taken it again and now injector 1 and 3 are showing up. The thing is the car is driving perfect and is not performing any less at all plus it's only got 36k on the clock.

We know injector 1 was replaced just before we bought the car last year yet this was showing up along with injector 3.

We've got it booked in again and we've been told they'll have to strip the injectors off and test them failing that we may need new injector or injectors.

I've had a search round on the net and have noticed a few issues with the injectors on the blue efficiency models. Have I any chance if I spoke to Mercedes? Surely they shouldn't go at such low mileage.

Considering we had the last one for 8 years or so and had no problems at all it is very annoying, plus we've just moved feckin house so the timing could have been better

 

[Steve@Avantgarde]

You can check injector performance on STAR diagnosis which will show its quantity correction values and whether they are in spec. You can also do a leak off value test with the injectors in situ. There is no need to remove the injectors to test them.

You havent said if your garage is a MB specialist or not but if he isnt then maybe seek an opinion from a MB specialist. Unfortunately these will have the later type piezo injectors and they cannot be overhauled, it will be replacement only.

Although you would expect injectors to last for much more than 36k miles, the reality is that it is a fallible part of the diesel system and can fail at any mileage, I have seen injectors fail at 1000 miles before now. I think you have just been unlucky.

You can try your luck with one of the dealers but i fear at 6 years old, they will offer no goodwill.

 

[lewisg]

Hi Steve,

Thanks for the reply.

It's not a indy no, it's our local guy who we have used for years. I've had it in today and he said it def needs injector 3 replacing.

It may need the injector replacing that it had done before we bought it if it turns out to be a crappy one as this is flagging up on the computer.

He said we are looking around 3 hours labor to strip them down and then the injectors themselves are about £150. He's said it's our call but at that point it maybe as well replacing the other 2 injectors at the same time due to the work involved stripping it down.

He's going to need it for 2-3 days ideally so he's just called to check we are ok with it all with us recently moving etc.

He said they'll test them all first and give them a ultrasonic wash? and then see how well the others are performing at that point.

I tried the MB dealer and got nowhere, i'd think twice about getting another one of these feckers after this - bring back the old one

 

[lewisg]

Update: :-(

Righty we had the injectors looked at and when checked they were all in spec. The mechanic said they where within 0.001 of each other or something along them lines. They've put them in a ultra sonic wash just to see if some much had got in.

Apparently it was hard work getting to them but we collected saturday and the bill was £240 far lees than we'd expected. Anyhow we thought that would be it.

The mechanic mentioned it was weird for the o% pressure fault to be showing due to them all being in spec so he put it all back together and said to see how it goes and if not he'll have to have a look at some other routes.

We set off from the garage and the little fecker came on again! It's soooooo annoying, again the car itself is driving fine and isn't in limp mode. It's doing our head in we never had a problem with our old A Class.

Any thoughts on what it could be?

Thanks

 

[Steve@Avantgarde]

What you need is someone with STAR diagnosis and experience of MB's. A fault code check is always the first place to start. It sounds like you are taking it to people who are playing a very bad guessing game and lightening your wallet without actually getting to the bottom of the problem.

If you knew or could post some fault codes then that would help. I have had some A classes with wiring issues causing misfires but again that is another guess. The EML light comes on for a reason, something is not right and it needs a professional to fix it.

Use the Mercedes Specialist finder in the top right hand corner of the page. Most Independent specialists listed there post on this forum so you can have confidence in their ability.