Download Direct-Hit 1995 Oldsmobile Cutlass Supreme 3.1L Test Details Hotline Archive # 97688 Confirmed Fix Vehicle Application: 1993 Chevrolet Camaro 3.4L 1995 Chevrolet Camaro 3.4L, Vin S 1994 Buick Skylark Custom 3.1L, Vin M, Eng Cfg V6 1995 Chevrolet Lumina 3.1L 1994 Chevrolet Corsica 3.1L, Vin M, Eng Cfg V6 1995 Pontiac Grand AM SE 3.1L, Vin M, Eng Cfg V6 1994 Oldsmobile Cutlass Supreme S 3.1L, Vin M 1995 Pontiac Grand Prix SE 3.1L Customer Concern: DTC 77. Tests/Procedures: 1. Remove the throttle body, and inspect the Exhaust Gas Recirculation Valve (EGR) port in the intake plenum. 2. The passage plugs at the bottom where it dumps into the plenum. 3. Best to use an old speedometer cable in a drill to run inside the passage to knock all the carbon out. Potential Causes: Restricted Exhaust Gas Recirculation (EGR) Passages Tech Tips: When an EGR solenoid is activated by the Powertrain Control Module (PCM), the PCM monitors the change in the Manifold Absolute Pressure (MAP) reading. Carbon deposits anywhere in the EGR passageways will set this code. Diagnostic Codes: 77 Author: Christopher Pittman Average Reported Mileage: 144715 Confirmed Fix Summary Confirmed Fix 13 – Exhaust Gas Recirculation (EGR) Passages 2 – Exhaust Gas Recirculation (EGR) Valve 1 – Exhaust Gas Recirculation (EGR), Exhaust Gas Recirculation (EGR) Passages 1 – Exhaust Gas Recirculation (EGR) Passages, Exhaust Gas Recirculation (EGR) Valve Confirmed Fix Details Tech Reported Fix Details Confirmed Fix Chris Garbett February 28, 2008 1995 Oldsmobile Cutlass Supreme, 3.1L, Vin M Exhaust Gas Recirculation (EGR) Passages – cleaned passages with cable and drill. test drive proved fix. Exhaust Gas Recirculation (EGR) Passages Craig Bergemann February 03, 2010 1995 Oldsmobile Cutlass Supreme, 3.1L, Vin M Cleaned Exhaust Gas Recirculation (EGR) Passages – CLEANED RESTRICTED EGR PASSAGES Exhaust Gas Recirculation (EGR) Passages Tech September 20, 2007 1994 Pontiac Grand AM, GT 3.1L, Vin M, Eng Cfg V6 * Cleaned Exhaust Gas Recirculation (EGR) Passages – Code 77 EGR testing passed. Removed EGR decarbonized valve, intake, exhaust tube and serviced throtle bore. Problem fixed. Exhaust Gas Recirculation (EGR) Passages