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Home >> Chevrolet >> 1988 >> Spectrum Express >> Repair and Diagnosis >> Engine Performance >> System >> 1.5L EFI Turbo >> Trouble Shooting >> Component Testing By Trouble Code >> Code 33 (MAP)
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Code 33 (MAP)

  1. Clear codes. Start engine and run for one minute or until check engine light comes on. Turn engine off. Jumper ALDL and turn ignition on.
  2. If code 33 is present, clear code. Disconnect MAP sensor connector. Remove ALDL jumper. Start engine and run engine for one minute. If check engine light comes on, jumper ALDL and note code.
  3. If code 33 is present, check for short circuit in Green wire MAP sensor connector and B11. Repair harness or replace ECM.
  4. If code 34 is present in step 2), check for plugged or leaking vacuum hoses to MAP sensor. If vacuum hoses are good, check for open in circuit B18 to MAP sensor Red wire harness terminal. If harness good, replace ECM.
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