Smoking Issue

[PitViper83]

I Bought my 1st DSM a month ago (98's GST 149,000miles Auto). Everything on the car is stock except intake, exhaust, and Greddy Type-s.

Previous owner told me he was running full synthetic. So last Thursday I performed an oil change using Pennzoil Synthetic.

Later in the day I was running some errands and left the car running while I ran inside to handle some business. When I returned I noticed the car was blowing a small amount of smoke out of the exhaust. Then, when i got in and revved it up, it blew a large plume of smoke out. The smoke ONLY shows when I'm at idle (i.e. sitting at a long stop light). Too, the oil pressure seemed low (although I must preface this by saying that I didnt really pay attention to it until this problem flared up). There is a little mark on the oil pressure gauge about a third of the way up and it doesnt reach that mark unless I am around 3500-4000rpm. at idle, oil pressure is almost zero. Is this normal?

The smoke smells of burning oil. It does NOT have a sweet coolant burning smell to it nor is there any white ash left on the inside of the exhaust tips.

Also, the car does not overheat or run hot and turbo seems to be spooling the same as it has been.

Now, Wednesday I changed the oil back to regular 10-30 and since then - no smoke.

What I am worried is that while the smoke is gone that there may be a bigger issue brewing and thats where I need your experience and help.

These are the things I thought it was/could be:

1. Head gasket: But like I said, the smoke doesnt have that sweet smell and there is no white ash on exhaust tips. Also I have felt all around the HG and find no leaks.

2. Oil pump/sending unit fouled: usually when the oil pump is going out or clogged you can hear a loud hum. and I dont hear anything

3. Rod bearings: Again, this would make the engine loud and clanky. i hear none of that

4. Seals: Very well might be my seals. No, I have not done a compression check. Planning on doing it on Tuesday

5. Valve guides: I would hear valve chatter and I dont. The engine runs very quietly.

6. Finally, my Turbo: This is my first turboed car. Not sure why if my turbo was going out why I would show low oil pressure. But thats why I need you guys' help.

Sorry for my long post. Any help is greatly appreciated.

 

[blazindominic@n]

What color is the smoke? If its not white it probably isn't your head gasket

 

[DSM1G90]

Nah ... worn valve seals.... 149K miles on an original motor usually spells hardened valve seals.

Until for now until you get the seals replaced, use Vavoline, or Castrol 10w30 dino oils...

When you get the seals replaced, stay away from Pennz Synth. Mobil1 or AMSOIL are the better choice, and if you like blowing money like a poor man who loves to think he's rich, a lot use the way overpriced Royal Purple Synth products.

 

[blazindominic@n]

Or the turbo seal is starting to go bad, that was my first thought but i wanted to try and get more information. Also check your feed line if its kinked it may cause your turbo not to get enough oil at idle and once your at a higher RPM the pressure pushes more oil to the turbo. My friend had this problem.

 

[eclipsalon]

just wanted to say thanks to the op for stating all he thought might be wrong. it made me realize i might have a bad oil pump? it either that or rod beaarings which would lead to the famous crankwalk?

 

[dlm009]

i had this problem also sounds like your valvestem seals mine was easier diagnosed bein a 5 sp it only smokes at idle or when i down shift it creates vacuum and sucks oil past the bad seals so if i turn off the car right after and the oil sits in it the next morning all that oil burns out as smoke it also did it at traffic lights everytime i stopped before my mmechanic friend told me just dont down shift till its fixed an tht worked for me so far

 

[PitViper83]

What color is the smoke? If its not white it probably isn't your head gasket

The smoke is grayish/white in color but I guarantee it isnt my head gasket. I am not a certified mechanic but do have a decent level of mechanical knowledge/experience being 29 years old and on my 21st car. 2 of the 21 had blown the head gasket at one pooint, and from those experiences I know this car is not exhibiting any of those signals.

I do think it is entirely plausible that its one of these three things:

1. Piston Rings
2. Valve Guides
3. Turbo

I am leaning turbo because if it were valve or piston ring related then I would be experiencing more of a "blow-bye" scenario where I get smoke when I'm both driving and stopped at idle. Am I wrong?

I'm actually hoping its turbo so I have an excuse to upgrade.

 

[mnelsen]

all youre assumptions are wrong except for valve seals. if it's at idle then your turbo isnt spooling. so it wouldnt burn that much oil. if it was your headgasket then youd be burning a little coolant too and it'd more than likely be running a little warmer. lucky for you valve seals are easy