exaust odour - Cdi

[m2mb]

Gentlemen,

I would appreciate it if you give me your knowledgeable opinions on the subject below

My car, a 56reg Cdi 220 w211 gives out an exaust odour best described as pungent-acidic (with a CO/CO2 feel to it like when your are close to a gas heater - it does not smell like unburnt or raw fuel). This seems to even disturb cars behind me since I noticed they keep some distance at traffic lights! I notice it in the car also (!) when I reverse as well but not in other occasions (so far). It does not smoke or has any other issues that i noticed of but again I rarely accelarate hard or push it in any way.

any ideas (cat maybe)

many thanks,
mb.

 

[Troon]

From the exhaust pipe, or from under the bonnet and noticeable in the car?

If the latter, my guess is leaking injector seal(s). Open the bonnet, pop the engine cover off, remove the foam injector noise insulator (if fitted) and see if you have black gunge around one or more of the injectors.

If you do, your local friendly indie should be able to sort this out for you for the right side of £100, if it's just the one, assuming the injector comes out easily and isn't damaged. I had this on mine, with a strong "fumes" smell inside the car whenever I stopped.

 

[m2mb]

thanks for the reply troon.

I dont know really (can not pinpoint - havent paid much attention yet) where this smell is coming from but I can smell it under the car and not just off the exaust - i am not even sure it is from the exaust.

nice car (and consumption, in your link)

m

 

[renault12ts]

Diesels are not particularly pleasant smelling. But, if it's really bad and noticeable, I would suspect a leaking injector seal. Not an expensive fix, but don't leave it.

 

[Troon]

I dont know really (can not pinpoint - havent paid much attention yet) where this smell is coming from but I can smell it under the car and not just off the exaust - i am not even sure it is from the exaust.

Then you need to follow my advice and check out the state of the injectors. As renault12ts says, you don't want to leave it or you'll end up with an injector encased in hard sticky tar, which will take longer (and thus cost more) to fix, as well an increasing the probability of damaging the injector.

 

[m2mb]

thanks guys ,

i will have it checked

 

[Troon]

thanks guys ,

i will have it checked

Whilst you're free to spend your money "having it checked", it truly is trivial to check it yourself. Apologies if any of the steps below are teaching you to suck eggs, but I like to encourage people to learn:

1. Open bonnet: Pull the handle that's by your right knee whilst sitting at the wheel. You need to pull fairly hard, there'll be a couple of clunks. At the front of the car, you'll see a little black plastic T-bar handle protruding from the grille. Pull that, and lift the bonnet up by the grille. There's no support strut - it holds itself up.

2. Remove big black plastic engine cover. On the 220CDI at least, it just pulls off, upwards - it's supported by four (?) push-on clips at the corners. Do this with the engine off and beware of hot bits if it's been running recently.

3. You'll then see a foam block sitting roughly on the centre top of the engine. Lift that off, and you are looking at the injectors - the four black things sticking into the top of the engine with metal fuel pipes going to them.

You should be able to see down to where the injector disappears into the metal cylinder head. If any of the holes is full of black sticky gunk, that's your problem there.

Putting everything back together is the reverse of how you got it apart. To shut the bonnet, just drop it from about 12".

Hope that helps!

 

[renault12ts]

An even simpler thing is to lift the bonnet (as described above) and if you observe smoke emanating from the engine cover then you have the problem.

 

[m2mb]

I tried to reply last night with my 'smart'-phone but to no avail due to typing/editing problems with the phone's screen (my personal laptop was stolen (yeap) from the house some months ago and have not bought another one yet)

Anyway, I openned the bonnet last night, started the engine, observed for several seconds (with the lid on however as I could not open it with a mild pull - my previous car's cover was held in place with four plastic bolts) - no smoke or any smell from there. However the engine was cold - dont know if this matters-should I leave it to warm up?

I will try to put some more heart into it and pull the cover open to have a look at the injectors although this is out of my skills domain.

Nice instructions Troon - thanks.

r2tl you sure smoke would emanate from the engine top? - this sounds really serious and I suppose I would have the smell inside the car as well. But as said above, no smoke from the engine seen.

I notice this smell, which is very very characteristic (cannot confuse it with any other smell on older diesels or petrol engines) everynow and then near newer diesel cars - and I suspect only common rail ones, which makes sense to lead to the injectors.

If a cat conv is failing would there be a smell??