O. Road Test Procedure

1991 Volkswagen Jetta L4-1984cc 2.0L DOHCSECTION O. Road Test Procedure
O. Road test procedure

In order to ensure that no Diagnostic Trouble Code (DTC) exists in the On Board Diagnostic system after all checks and repairs have been completed, the vehicle must be road-tested according to the following procedure. Adhering to the stated specifications will allow the system to operate those control functions which are monitored by the On Board Diagnostic System (OBD).

- Test drive car for at least 10 minutes.
- Coolant temperature must exceed 80~C (178~F) for at least 3 minutes.
- At engine speed above 4600 RPM, press accelerator pedal briefly all the way down.
- In 4th gear, starting from approx. 30 MPH, accelerate for about 4 seconds with gas pedal pushed half way down.
- After completed road test, connect Engine Scan Tool (ST) VAG 1551 once more and check DTC memory.
^ if a malfunction (DTC) is indicated, correct as required (refer to initial fault code printout, see page 2)
^ if NO DTC is indicated, disconnect Scan Tool and visually check that all hose connections and wire harness connections are properly secured.

- Close engine hood.
RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.