Engine runs at 4,000 rpm 1996 GMC Suburban 4×4

Chevy Suburban

My Suburban wasn’t starting so I changed the Distributor and Rotor.  It started but it runs at 4,000 RPM’s. I put a code scanner on it and got a P0102 code so I used Mass Air Flow Cleaner on it and tried again. Same thing, 4,000 RPM’s but no codes this time. Can you give me an answer because I’m stumped! I looked at the throttle spring and it seems to snap back OK, please help. It is a 1996 GMC Suburban 4×4 4 door Automatic with a 5.7 liter engine.


The engine running with a high idle is a classic description of a vacuum leak.

Chevy Code P0102

Mass Or Volume Air Flow A Circuit Low Input

Probable causes

  1. Sensor or solenoid faulty
  2. Connector terminal contact is damaged or corroded
  3. Wire harness – Check harness for correct voltage, open, short to ground or short to voltage
  4. Update control unit software – Check for the latest control unit update
  5. Powertrain or Engine Control Module faulty
  6. Battery voltage low