Carbon smoke?

[DeadRS]

Hi all. I have a 97 RS that I am slowly going through. For the past 4 or 5 months, I have been seeing a lot of smoke once I reach operating temperature. It definitely isn't oil, and I have had numerous mechanics look at it, all coming to different conclusions. I have been trolling these boards since I purchased the car a little over a year ago, and haven't found any thread that is exactly like what I am experiencing. At initial startup, the car runs flawlessly, no sputter, hesitation, or smoke, once it warms all the way up, then it just starts billowing smoke, yet still runs fine other than the smoke. Too be 100% honest, funds are a little low at the moment (Christmas), so if anyone here could point me in the right direction, or at least give me some ideas I would greatly appreciate it. The smoke is hard describe, not blue like oil, and not white like antifreeze. Kinda somewhere in between, and at times nearly black. And as the title of the post suggests, it smells like carbon smoke.

DeadRS

 

[cimotorsports]

Hmm, does it smoke heavily when decelerating? If it does it could be valve seals.. usually if its black that means its getting way to much fuel.. maybe a sticky injector, can u smell fuel? Normally when we get symptoms like that well do a compression test and a leak down test and go from there.

 

[DeadRS]

It actually seems to smoke most when I am stopped (Drive-through, Stop sign, etc..) I haven't been able to smell fuel at all, just the heavy carbon smell. I really don't have the money to have a compression, or leak down test done, but I'll see what I can swing in that department. Thanks much for taking the time to respond with a few ideas. It is appreciated.

 

[cimotorsports]

Hmm im willing to bet either valve seals or worst case the rings.. how many miles are on that engine.. valve seals usually start to go bad at 80k rings about 100k depending on hard it was beat on

 

[DeadRS]

Well the engine has 105,000 approximately. Knowing my luck, it will be both of the aforementioned possibilities. Will a compression, and or leak down test pin point the culprit?

 

[4UH8ERS]

Well the engine has 105,000 approximately. Knowing my luck, it will be both of the aforementioned possibilities. Will a compression, and or leak down test pin point the culprit?

most likely yes. The compression test is rather cheap and simple and you can do it yourself.

The leakdown test on the other hand is more difficult and time consuming, although if your compression test turns out good that will definately be your next test that needs to be done.

 

[1.8laser90]

my car smokes just like yours, it also has that smell to it. Ive diognosed that its my valve seals. my engine has 150k on it, but mine just started all of sudden which i never quite figured out, it started right after i installed my header and cat, i took it down the road and of course i was testing my header and cat out and the next day when i let it sit and idle while i was looking for somthing and i came back it was smoking pretty decently out the exhaust and has been ever since which was about 4 months ago.
its gotten alot worse now but sometimes it will stop but come back the next drive ? It doesnt smoke when its cold and doesnt puff anything out when it first starts. Im taking the head off over christmas break and rebiulding the whole top end. hope this leads u somewhere

 

[DeadRS]

A big thanks to everyone that took the time to respond on this. I will see about getting the tests done, and let everyone know what the outcome is.

 

[DeadRS]

Compression test as follows:
1 - 150
2 - 63
3 - 147
4 - 153

The guy that did the compression test for me said that it is possibly the headgasket, and it appears be losing compression on the exhaust side. Any advice as to how to proceed would be appreciated, as he wasn't 100% sure that was the problem.

Thanks in advance,

DeadRS

 

[cimotorsports]

Yep number 2 is def down low, i would check the headgasket for damage, if none is present then i would assume its your rings or worst case even a cracked valve, let us know what you find when you get it apart