[drewden]

Hey guys, i have noticed a lot of black on my tailpipe but there is no visible smoke coming out. i took it in to the shop but they said not much they can do about that because it's all computerised. It does have a lot of miles on the clock though. Any ideas from the pro's.
God Bless you Rav-ers

 

[SZRimaging]

It means that you are burning oil somewhere in the engine. It is probably internal, so it would be hard to fix. Not saying it isn't possible, just tough. It has nothig to do with computers. Most likely it is a seal or ring of some sort.

 

[drewden]

Well i do have a lot of miles on it, so you may be right.
Thanks.

 

[Bluenoser]

Both my '98 and my current '05 RAV's had/have black soot in the tailpipes, and I always figured it was just inefficient combustion due to driving style or something......
If your not adding oil between changes, I'd figure it's normal.....
I traded my '98 at 150k kms and it still wasn't using any oil.....
Since they took the lead out of gas, I can't read the color of a tailpipe........leaded gas= ya gotta be old to remember... :lol:

 

[VeroLAN]

Seen it on every car I've owned, unless it is excessive it's no big deal.

 

[rav97]

Mine has the same problem, in that it uses a bit of oil, has a "sooty" exhaust, but blows absolutely no smoke (even if i rev the living daylights out of it).

One thing I cant understand is if it is burning oil, shouldnt there be visible smoke?

 

[SZRimaging]

Mine is the same way, it burns off about 3.5 quarts for every 4000 miles, but you never see a puff of smoke from it. Tailpipe is as black as can be though. I figure it is cheaper to let it burn the oil (when I need to add more it is time for a change anways), than it is to actually fix the problem. (We ran dye through it and couldn't find visible leaks, meaning the problem was internal....ugh.)

 

[rav97]

So what could be the cause?

Piston rings?