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98ACR
12-15-2006, 09:36 PM
Lots of blackish-bluish smoke coming from the tailpipes. The inside of the exhaust is coated in a thick black tar-like substance. Spark plugs have brownish ash on the electrode, tip, and ceramic insulator; the rest of the plug is covered with same tar-like substance. Oil consumption is roughly 1 qt per 500 miles. No oil leaks. 178k miles. Head replaced at 140k miles due to broken T-belt.

Does this sound like rings? Well, it does to me....the new car hunt has begun. The G will get a 4g63....eventually, right now I need reliable transportation.
seth98esT
12-15-2006, 09:42 PM
Smokes even at idle or just under acceleration?
6G72gearhead
12-16-2006, 01:09 AM
From those symptoms it sounds like your burning oil.
RedGalant2k1
12-16-2006, 01:28 AM
From those symptoms it sounds like your burning oil.

Most likely from blow-by past the worn piston rings.
DOHCstunr
12-16-2006, 01:40 AM
i'd do a compression test first.
dry then wet.

possible issues...

leaking valve seals,

clogged pcv valve creates too much crankcase pressure and results in blowby,

worn piston rings,

worn main/rod bearings.

its all speculation till you bring back some raw data.
bronxbombr
12-16-2006, 04:20 AM
valve stems,seals, maybe valve cover or oil pan gasket is worn and oil is leaking down the crossmember to the downpipe and burning there.
4-G-rim
12-16-2006, 08:38 AM
I would do a compression test. Replacing your PCV valve won't hurt..its a cheap replacement anyways.

I am calling either bad valve seals or piston rings are failing.
98ACR
12-16-2006, 09:15 PM
It smokes from idle to redline. Worse when it's cold..goes away slightly once engine warms up.

I've tried 3 different PCV valves, I've even tried removing the PCV entirely letting the crankcase breathe 100% freely.

The head is "new", it was completely re-conditioned before re-instaling it.

Compression is supposedly within specs, though I guess I can try it myself later this week and bring the #s

I'm leaning most toward rings since the milage on the block is so high and the engine is still running so strong.
DOHCstunr
12-16-2006, 10:04 PM
idk why you ahven't compression tested it yet.
jeez
RedGalant2k1
12-17-2006, 12:56 AM
How often are you replacing your air filter?

My old S10 had blow-by so much so that I had to replace the air filter at each oil change every 3,000 miles.
bronxbombr
12-17-2006, 06:05 AM
idk why you ahven't compression tested it yet.
jeez

COSIGNED!!!