cerberus1971

94 d15b7 95k miles, 120 pounds compression across all 4 cylinders, PCV clean and making vacuum. When the oil cap is off it literally sprays oil, and running it smokes like crazy. Burns a quart in 100 miles. Runs like a top, still gets 43 mpg. Any ideas?? Is the engine shot?? PLEASE HELP. Thanks!

Former User

Probably bad valve stem seals.

cerberus1971

Sorry, head just redone, and did same thing before head redone. Thanks!

F4MzEkSOL

piston rings probably out

F4MzEkSOL

what color smoke white or blue

Former User

I agree. Do a leak down test.

cerberus1971

Smoke is blue and definitely oil, it's burning a quart in 100 miles. PCV valve is new and making vacuum at the PCV, valve cover is clean inside and not restricted. Is there any other crankcase vent on this engine besides the PCV?

Former User

If you add a teaspoon of oil to the cylinder before the compression test, does the pressure increase substantially above 120 PSI?

F4MzEkSOL

blue means piston rings are out ,white means the car has been dead or never been running for a while white is actually moisture

F4MzEkSOL

i had the same problem in my brother gsr and then he did a full internal replacement( rings,bearings, etc..) after that it stops draining oil

cerberus1971

What throws me on this is how good the thing runs, and the mpg, it just doesn't act like rings in my mind....I've not wet tested the cylinders, but compression is consistent even warm.

F4MzEkSOL

same with my brother gsr the car runs hard but until one day it stop running lol

Former User

If the wet compression values are much higher, then you have likely identified the problem as worn rings.

94EG8

I put a headgasket in my first D15B7 (was burning miniscule amounts of coolant but never smoked, car ran fine) as soon as I started it, it was burning oil, a lot of oil. It would take around 3L of oil in under 100kms, you couldn't even see the car for the smoke, but it ran fine. Ran it like that for 4 days and pulled the engine and replaced it with another D15B7, pulled the head on the first engine and didn't see anything wrong, never did pull the bottom end apart.

BryanM.

iTrader: (1)

A compression or leakdown test WILL NOT tell you if the oil rings are worn out. Their sole duty is to scrape excess oil from the cylinder wall to keep as much oil out of the combustion chamber as possible. Oil rings have NOTHING to do with compression.

sde780

most likely rings. compression numbers seem low, i just did my d15b2 they were around 185