LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Chevrolet >> 1990 >> Corvette Base, 2D Convertible, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Exhaust Gas RECIRCULATION (EGR) >> Digital EGR Valve
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Digital EGR Valve

  1. Start and allow engine to idle. With engine at normal operating temperature, disconnect digital EGR valve solenoid harness connector. Using a 12-volt power source, very quickly energize EGR solenoid No. 1. RPM should drop slightly. See Fig 1.
  2. Next, energize EGR solenoid No. 2. RPM should drop slightly more than step 1). If RPM drops, EGR is okay. If not, check for plugged EGR passages or defective digital EGR valve. Check EGR solenoid resistance. See DIGITAL EGR SOLENOID RESISTANCE table.

For additional testing procedures, see appropriate TESTS W/CODES article.

DIGITAL EGR SOLENOID RESISTANCE (1)

Terminals No. Resistance (Ohms)
A-D 20-30
B-D 20-30
C-D 10-17
(1) See Fig 1 for terminal location.
Fig 1: Digital EGR Solenoid Circuit
G90A09034Courtesy of GENERAL MOTORS CORP.