Intermittent smoke from the exhaust - 6 cyl

[jmonintwo]

99 GTZ, pretty well taken care of. Recently I've noticed smoke from the exhaust. Weird thing is, it does it completely randomly. It can be running with clear exhaust then all of a sudden some smoke...then a minute later it will stop smoking. It might smoke again in 5 minutes, it might not smoke for two days. Any thought???

[pinoyesv6]

what color is the smoke?

[jmonintwo]

semms to be mainy white...maybe a little grayish

[ipaintu]

valve leakage...????

[seth98esT]

White smoke = coolant
Blue smoke = oil
Black smoke = rich

Headgasket going?

[Djayfusion99_es_v6]

it could be oil if the seal of the spark plugs if it gets broke then smoke will come out of the exhaust...... wouldn't it? when was the last time u did a tune up was there oil on the plugs if there was its a spark plug seal.....maybe......

[seth98esT]

If its not blue smoke its not oil. Do a compression test.

[manybrews]

some white smoke is completely normal..
remember, half of normal combustion is water vapor! if its cool outside, you'll see white smoke.

provided you havent overheated your engine, the chances of some type of head or headgasket failure are about a million to one. it just doesnt happen.

[jmonintwo]

NOw I'm confused as hell, so today as I'm out and about I decided to leave the car running as I went inside to do some errands. Everytime I came back outside to the running car I could see light smoke coming out of the exhaust. When I would rev it up to see if it would smoke more, man did it. but then the smoke would go away after about ten seconds. I checked the coolant...full, I checked the oil a little low so I added some more, Checked the plug wires...they're all tight.....WTF! Is there a such thing as diagnostic codes on the 6cyl? Can I do it myself? Can a parts place do it? The closest dealer is about 30 miles away and I don't have all day to screw with them....

[bergundy2k1]

My guess it that your piston rings may be bad and they are not sealing the combustion chamber properly and letting oil into the chamber. The white smoke could be oil burning, this is usually prevalent in older cars, but galants seem to do this as well. My parents had an older galant, really old and that was a common problem with them. That may be your problem.

[manybrews]

how many miles on your engine?
youve just described worn valve seals. a telltale sign of worn valve seals is excessive smoke after extended idling, and a puff upon startup (usually).

worn rings usually only smoke heavy on deceleration

[jmonintwo]

I'm at 95,000. I would think that that's not a lot for that engine, especially since I've taken such good care of it...... When you say valve seal do you mean where the valve actually seats agains the head (at the top of the combustion chamber) or do you mean an actual seal (like a rubber seal)?

[manybrews]

I'm at 95,000. I would think that that's not a lot for that engine, especially since I've taken such good care of it...... When you say valve seal do you mean where the valve actually seats agains the head (at the top of the combustion chamber) or do you mean an actual seal (like a rubber seal)?
actual rubber seal on the top of the valve quide / valve stem.

[jmonintwo]

sounds like it's beyond me....I guess I'm heading to the dealer...unless anyone else has some thoughts....

[jay shafer]

mine is doing the same thing and i was told it is valve seals
but what basically needs to be done. Does it necessarily have to be taken back to the dealer to fix or can shop do it.

[seth98esT]

Valve seals are a PITA to replace. Have to remove the camshafts and then the springs and retainers. If you dont have the right tool to remove them with the head still on, it is pretty much impossible. You can make acheap tool to remove them with the head off the car, but to remove them with the head on the car you need a $200 miller tool. Maybe you can rent it somewhere, not sure.

Id take it to a shop or dealer to have them replaced. They are only a $15 part but are just a pain to replace with the head on the car.

And if your valve seals are bad, oil will leak into your exhaust and burn up. But the smoke will be bluish if it is burning oil...

[jay shafer]

how much u think Mits dealer will run me. Just an estimate

[manybrews]

just doing valve seals is in itself really a waste of money. Chances are good that the valve quides are also worn.
Basically, if I suspected oil from the valves, I would never do anything but a full valve job.
But you should get it looked at first. "internet diagnosing" is about as inaccurate as you can get.

[jmonintwo]

UPDATE - I appreciate everyone's advice...but let me tell you where I'm at. So I coudn't figure out the smoke. Take it to the local shop, guy tells me the rings are worn, says it's a notorious problem. Says I need to put some oil additive in it to get the smoking to stop and then trade it ASAP. So I'm getting pissed. It has 95K on it, but I've always taken care of it and it runs great. Anyways, after being ticked off all day, I call the dealer to see if it's by chance under warranty. They say no, why do you ask? I tell 'em about the smoke and what the local mechanic said. They say bullshit, bring it in, we aint herd of that before. So the dealer is about 40 miles away and I need gas. I fill'er up and start driving, By the time I get there I've used a quarter of a tank! I tell the service manager about the smoke and the heavy fuel consumption, he chuckels and says "son, that aint smoke...it's water vapor. You've got an injector stuck open (I think)." He says it's running waaaaay too much fuel through the injector(s), the fuel can't all be burnt, so it's passing through the cadillac converter (which can't handle all the unburnt fuel), trying to get burnt up in the converter and coming out as vapor. Says he'll pressure test the system, fix the problem and she'll be good as new. So it's supposed to be ready tomorrow. I'll let you guys know how it turns out when I get home. Man...I'm outta breath

[dave1]

how did u fit a converter from a caddy in there

[seth98esT]

<div class='quotetop'>QUOTE(dave1)</div><div class='quotemain'>how did u fit a converter from a caddy in there</div>
:lauging:

[manybrews]

okay, thats more like it

first of all, they arent "notorious" for ring wear. Quite the opposite, mitsus lower ends (cranks, pistons, etc) are among the BEST IN THE WORLD. (no joke).
In 15 years, do you know how many ring problems Ive seen?


one.


even on engines with 200K, the rings (provided the car has been maintained at least a little bit) look fine.



now, the injector. thats much more likely. I just had one on a diamante (and thats the second Ive seen in 2 months).
The dealer is no doubt completely correct, and like usual, the little "mom and pop" fixit shop is run by morons.

[jmonintwo]

Back from the dealer, and so far so good. It still had some crap blowing out the tailpipe, but the srevice manager said it was from excessive carbon build-up. He said drive it a couple of hundred miles and let all the carbon get flushed out. By the time I got home I noticed the visible exhaust was much less. So I'm going to hope it keeps getting better and eventually clears up. I've got to drive it about 500 miles this weekend. I'll let everybody know if it improves over the weekend. Thanks again for the forum guys. This site has been a real benefit to many Galant owners.

[jmonintwo]

Back from the weekend and the problem is gone! She's back to her old self...Thanks again TGC members...