EEC IV - Self Test Code 34 Verification

Article No. 85-8-26


EEC-IV SELF TEST CODE 34 - VERIFICATION - (2.3L) EFI


LIGHT TRUCK 1985 RANGER

CALIBRATIONS: All 2.3L EFI
WARNING: This modification is authorized only for the listed engines. Performing this modification on other engine calibrations is unauthorized and could create liability under applicable federal and local laws.

When performing engine running quick test, a code 34 indicates that, with engine RPM elevated and stabilized, a specified RPM drop did not occur when EGR was turned "On".

Properly operating vehicles may indicate a code 34 if the engine RPM does not drop fast enough. To verify EGR flow, follow this procedure.

^ Tee a vacuum gauge to EGR valve vacuum line.

^ Initiate engine running quick test.

^ Observe vacuum gauge, vacuum should increase to greater than 5 in. hg. and indicated moderate engine roughness (this test confirms EGR flow) ignore code 34.

^ If vacuum is less than 5 in. hg. or engine does not indicate a moderate roughness (either could indicate no EGR flow) go to the Engine Emission Shop Manual to service code 34.

OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: "INFORMATION ONLY"