Fuel - Tank Won't Fill to Capacity/Gauge Stays On Full

File in Section: 6E - Engine Fuel & Emission

Bulletin No.: 73-63-14

Date: June, 1997

Subject:
Fuel Tank Will Not Fill to Capacity/Fuel Gauge Stays on Full for Extended Period or Fluctuates (Replace Fuel Level Sensor and/or Fuel Tank)

Models:

1997 Cadillac Concours, DeVille, d'Elegance, Eldorado, Seville
Built Prior to the Following VIN Breakpoints:

Model VIN Breakpoints

Concours/DeVille/d'Elegance VU275620
Eldorado VU614344
Seville VU828033

Condition

Some owners may comment on the following condition(s) relative to the fuel system:

A. Short fill/inability to fill the fuel tank completely (i.e, only 17-18 gallons (64-68 liters) maximum) or fuel gauge will not display full (F) or comes off full (F) too quickly after fill-up.

B. Fuel gauge stays on full (F) for an extended period and may show a sudden drop from full (F) to a number lower than 17 or 18 (for gallons) or 64-68 (for liters).

C. Fuel gauge reading is erratic (does not include minimal fluctuation noted during normal operating maneuvers such as braking, turning, or accelerating).

Cause

Condition A may be caused by a fuel tank mis-build. Condition B may be caused by an open in circuit 30/552 or a fuel tank mis-build.

Condition C may be caused by inaccurate resistor values in the fuel level sensor.

Correction

For Condition A

Replace the fuel tank with P/N 25663120. A new fuel level sensor kit consisting of the fuel level sensor and float arm assembly has been released as P/N 25314217 and should also be installed at this time.

For Condition B

- First check for an open circuit at connector C415 or in circuits 30 or 552 between the sender and PZM. (Refer to Section 8A-51-1 of the Service Manual).

- If no open circuit is detected, then repair as in correction for Condition A above.

Important:
Refer to the appropriate service procedures in the Service Manual, Section 6 - Engine Controls - 4.6L, to replace the fuel tank and the fuel level SENSOR assembly (not to be confused with the fuel SENDER
assembly).

For Condition C

Replace fuel level sensor and float arm assembly on the fuel sender assembly with fuel level sensor kit, P/N 25314217.

Refer to the appropriate service procedure in the Service Manual, Section 6 - Engine Controls - 4.6L, to replace the fuel sender assembly.

Important:
Assure the new fuel sender assembly seal included in the parts kit is installed.

Parts Information

Description P/N

Fuel Tank 25663120
Fuel Level Sensor Kit 25314217

Parts are currently available from GMSPO.

Warranty Information

For vehicles repaired under Warranty, use:

Labor Operation Labor Time

L1200 Use published labor
operation time.