Oil Burning and Running Rich - Broken PCV Hose and Disconnected Vacuum Lines

Enginebeginner✓ OP Confirmed

Problem

1987 NA (7MGE) with W58 swap was burning excessive oil (3 quarts over 1,000+ miles of highway driving) and running rich with loss of power at high RPM

Burning approximately 3 quarts of oil over 1,000+ miles of highway drivingSmall puff of smoke from exhaust after sitting for extended periodsHard starts when coldSmell of rich exhaustLoss of power at high RPMO2 sensor was found unplugged (plugging it back in initially changed nothing due to other issues)

Root Cause

A busted 3/4" hose running from the front of the valve cover (next to the oil fill cap) down to the base of the block was allowing oil to spew out and crankcase pressure to go unregulated. Additionally, multiple disconnected vacuum lines were causing the engine to run rich and lose power at high RPM.

Confidence

Moderate confidence — Original poster confirmed this resolved the issue

View Original Thread →Posted May 2021 on SupraForums.com