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MK3 / A70 markets
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Troubleshooting assistant

Pick a problem area, choose the symptom, then follow the remedy links or step-by-step TSRM procedure.

Diagnostic codes
Searching in 1990 USDM TSRM.
Areas /Engine backfires — lean fuel mixture
Step-by-step TSRM procedure

Engine backfires — lean fuel mixture

Follow the TSRM flowchart on FI-19.

FI-19
Current check

Check diagnosis system

Check for output of diagnostic code.
(See page FI-23)
Normal code

No diagnostic code

Continue with vacuum leak checks.
Malfunction code(s)

Diagnostic code present

Diagnostic code(s) (See page FI-26)