Hi,How you all doing! Can some one please tell me if it's normal to see some smoke come out the exhaust pipe when accelerating hard. I have a 1999 A4 48k. Just put it in for the 60k miles service.

 

Black smoke? That is indicative of fuel not being burned in the engine and getting into the exhaust. Any mods? It would be far more common if your car was modded and you were purposely running too much fuel to your engine. If you are not modded, I would go with indicative of a possible problem. What problem you have is a tough call. It could just be you are running a little rich. I could be spark plugs are dying. It could be a faulty sensor. No Check Engine/ codes, I would go with spark plugs.
Best guess with out more info. What engine do you have? What mods? When was the last time you tuned up? (Do you know what was done?)

You have to be sure it is black smoke though. Blue is bad, white is bad.
You weren't next to a diesel were you? What kind of fuel are you running (brand and where you live (country/city) and octane) Some country dealers do some weird stuff to keep their gasoline fresh longer (low volume sales)

 

Might be something silly like crappy sparkies? If it's black, then it's the best coloured smoke to have. White & Blue smoke rate pretty high on the "Oh-****-o-metre"

 

Thanks. But why is black smoke good? It juss looks worrying but not a lot comes out. Do you think the 60,000 mile service would get it sorted out.

 

It is not that the black is necessarily good, but not bad.

White means water is getting into your combustion usually a sign of cracked heads or bad seals. Same with blue smoke except that oil is getting to the combustion chamber.

Fuel is supposed to be in your combustion chamber so atleast nothing is broken.

But, you are not burning all your fuel. It would usually be a warning sign.

60K service might find it, but might not. If it is only under hard accel, it would be pretty unlikely for a run of the mill dealer to catch. If it is just spark plugs they should catch it (and for having 48K) I am guessing you have not replaced your spark plugs yet. So maybe just throw in "could you check the spark plugs," it will take them 2 minutes. If your car feels a little sluggish, and idles roughly (rpms bounce a little) these are the signs of old spark plugs.

 

^ ^ indeed!

Do not underestimate the havoc bad plugs & wires can wreak!

 

So here is a question more directed to whomever is reading this, but I just replaced my plug wires (200$) and the box says they are lifetime guranteed so do they really need to be replaced as often as the plugs? My A6 has 175K on it so apparently someone thinks that is the lifetime of the car. But, the things really were gone, there was so much resistance in the wires, the wires were making a clicking noise everytime they got spark. Ha ha ok, so the dealer never changes your wires for you either. And heck mine lasted to 175K miles so I think they are good to go for a while. Are you A4s running the same plug wires? super thin (5mm) super expensive (compared to most cars run double the thickness and cost about 30$)?

 

Dont be cheaping out on the Wires and plugs. Cos you all sorts of grief after a little while.