Faulty Fuel Guage

[wecampbe]

Have a 2000 Deville DHS. The fuel guage reads half full when the tank is full. Anyone have any ideas on whether its the cluster or the tank unit or something else. Is there some testing I can do to narrow down the problem. Thanks!

[MWA]

Check the OBDII codes for PO463. My 98 Eldo and several others of this vintage are coming up with defective fuel sender units. Mine made it necessary to pull the tank to replace the sender unit. Yours probably can be fixed with a sender unit kit with easier access on a 2000, but I am not certain. I think there was an elaborate thread on this some time ago by a GM mechanic...try the search at the top using fuel sender and/or the DTC# above. (Sorry, OBD=On Board Diagnostic and II is after 97, while DTC is Diagnostic Trouble Code) note: see also- Northstar Performance & Tech Section a few notches below for a "stickie" by Mcowden - "Got Codes, Look Here" for info on running the codes if you have never done it....tis easy!

[wecampbe]

MWA,

Thanks for the reply. I Pulled codes and the only current code is IPM B0269. Do you have any idea what an Instrument Panel Integration Module is? Does it control the fuel guage?

[MWA]

Try http://myweb.accessus.net/~090/dtcobd2.html Haukap's site it the best on DTC's and BO269 appears to be Air Inlet Door Range Error. Another great info site is http://myweb.accessus.net/~090/cadidiag.html I have the 98 three volume Eldo GM Shop manual, but it mentions no Intrument Panel Integration Module in that manual even though the above sources list it. Helm, Inc. in Michigan is the best source for a complete manual set for your 2000. Many find copies for less on ebay. My 98 manual has saved me thousands of dollars. Do you have "history" codes....those that are not "current" listed?

[OffThaHorseCEO]

how bout history codes wecampbe, i have the same problem and there are no current codes. the way mine happens is, if i fill up its all good, the tankw ill read ful etc etc

once i get to about 1/8th of a tank it gets stupid and fluctuates randomly between full empty half quarter and all in between.

once it does that i can check the codes and itll always be a history code sayin the voltage is wrong for the sender

[alanfeldkamp]

I have the exact same problem as wecampbe on my 2000 DTS. Checked for codes and have none present. Does anyone have any other ideas on fixing this problem?

[Caddyshack100]

Start with this

Document ID# 591099
2000 Cadillac DeVille


--------------------------------------------------------------------------------

Fuel Sender Assembly Service
Tools Required
J 34730 Fuel Pressure Gauge

Removal Procedure

Caution
Fuel Vapors can collect while servicing fuel system parts in enclosed areas such as a trunk. To reduce the risk of fire and increased exposure to vapors:

Use forced air ventilation such as a fan set outside of the trunk.
Plug or cap any fuel system openings in order to reduce fuel vapor formation.
Clean up any spilled fuel immediately.
Avoid sparks and any source of ignition.
Use signs to alert others in the work area that fuel system work is in process.


Caution
Provide proper ventilation when working with fuel in enclosed areas where fuel vapors can collect. The lack of adequate ventilation may result in personal injury.



Caution
Always wear safety goggles when working with fuel in order to protect the eyes from fuel splash.



Notice
Clean all of the following areas before performing any disconnections in order to avoid possible contamination in the system:

The fuel pipe connections
The hose connections
The areas surrounding the connections


Notice
Do Not handle the fuel sender assembly by the fuel pipes. The amount of leverage generated by handling the fuel pipes could damage the joints.






Relieve the fuel system fuel pressure. Refer to the Fuel Pressure Relief Procedure .



Drain the fuel tank (1) to at least ¾ of a tank full. Refer to Fuel Tank Draining Procedure .




Important
The fuel sender support assembly will spring-up when the locking ring is moved.


Remove the fuel sender assembly. Refer to Fuel Sender Assembly Replacement .
Disassemble Procedure




Note the position of the fuel sender strainer for installation (4).
Support the reservoir with one hand and grasp the fuel sender strainer with the other hand.



Pull the fuel sender strainer off of the fuel sender assembly.
Inspect the fuel sender strainer. If the fuel sender strainer is contaminated, the fuel tank should be cleaned. Refer to Fuel System Cleaning .
Discard the fuel sender strainer after inspection.



Disassemble the electrical connectors from the sensor assembly of the fuel pump and the cover assembly.
Disassemble the fuel level sensor assembly.
Assemble Procedure




Assemble the fuel level sensor assembly.
Connect the electrical connectors to the fuel pump and the cover assembly.
Assemble the rubber pad on the bottom of the fuel sender.



Position the new fuel sender strainer on the fuel sender and push on the outer edge of the fuel sender strainer until the fuel sender strainer is fully seated.
Installation Procedure




Install the fuel sender assembly. Refer to Fuel Sender Assembly Replacement .



Add fuel to the fuel tank.
Install the fuel tank filler pipe cap (1).
Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical.
Inspect for fuel leaks.
Turn the ignition ON for 2 seconds.
Turn the ignition OFF for 10 seconds.
Turn the ignition ON.
Check for fuel leaks.

Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.






Install the fuel sender access panel. Tighten
Tighten the fuel sender access panel bolts to 2 N·m (18 lb in).





Reinstall the rear compartment trim panel (1). Refer to Compartment Trim Panel Replacement - Rear in Body Rear End.
Install the spare tire cover, the jack, and the spare tire.
Install the rear seat cushion. Refer to Seat Cushion Replacement - Rear in Seats.



Install the fuel injector sight shield (1) to the engine.
Install the fuel injector sight shield nuts (2). Tighten
Tighten the nuts to 3 N·m (27 lb in).


--------------------------------------------------------------------------------
Document ID# 591099
2000 Cadillac DeVille

[Caddyshack100]

or this

Document ID# 591099
2000 Cadillac DeVille


--------------------------------------------------------------------------------

Fuel Sender Assembly Service
Tools Required
J 34730 Fuel Pressure Gauge

Removal Procedure

Caution
Fuel Vapors can collect while servicing fuel system parts in enclosed areas such as a trunk. To reduce the risk of fire and increased exposure to vapors:

Use forced air ventilation such as a fan set outside of the trunk.
Plug or cap any fuel system openings in order to reduce fuel vapor formation.
Clean up any spilled fuel immediately.
Avoid sparks and any source of ignition.
Use signs to alert others in the work area that fuel system work is in process.


Caution
Provide proper ventilation when working with fuel in enclosed areas where fuel vapors can collect. The lack of adequate ventilation may result in personal injury.



Caution
Always wear safety goggles when working with fuel in order to protect the eyes from fuel splash.



Notice
Clean all of the following areas before performing any disconnections in order to avoid possible contamination in the system:

The fuel pipe connections
The hose connections
The areas surrounding the connections


Notice
Do Not handle the fuel sender assembly by the fuel pipes. The amount of leverage generated by handling the fuel pipes could damage the joints.






Relieve the fuel system fuel pressure. Refer to the Fuel Pressure Relief Procedure .



Drain the fuel tank (1) to at least ¾ of a tank full. Refer to Fuel Tank Draining Procedure .




Important
The fuel sender support assembly will spring-up when the locking ring is moved.


Remove the fuel sender assembly. Refer to Fuel Sender Assembly Replacement .
Disassemble Procedure




Note the position of the fuel sender strainer for installation (4).
Support the reservoir with one hand and grasp the fuel sender strainer with the other hand.



Pull the fuel sender strainer off of the fuel sender assembly.
Inspect the fuel sender strainer. If the fuel sender strainer is contaminated, the fuel tank should be cleaned. Refer to Fuel System Cleaning .
Discard the fuel sender strainer after inspection.



Disassemble the electrical connectors from the sensor assembly of the fuel pump and the cover assembly.
Disassemble the fuel level sensor assembly.
Assemble Procedure




Assemble the fuel level sensor assembly.
Connect the electrical connectors to the fuel pump and the cover assembly.
Assemble the rubber pad on the bottom of the fuel sender.



Position the new fuel sender strainer on the fuel sender and push on the outer edge of the fuel sender strainer until the fuel sender strainer is fully seated.
Installation Procedure




Install the fuel sender assembly. Refer to Fuel Sender Assembly Replacement .



Add fuel to the fuel tank.
Install the fuel tank filler pipe cap (1).
Connect the negative battery cable. Refer to Battery Negative Cable Disconnect/Connect Procedure in Engine Electrical.
Inspect for fuel leaks.
Turn the ignition ON for 2 seconds.
Turn the ignition OFF for 10 seconds.
Turn the ignition ON.
Check for fuel leaks.

Notice
Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.






Install the fuel sender access panel. Tighten
Tighten the fuel sender access panel bolts to 2 N·m (18 lb in).





Reinstall the rear compartment trim panel (1). Refer to Compartment Trim Panel Replacement - Rear in Body Rear End.
Install the spare tire cover, the jack, and the spare tire.
Install the rear seat cushion. Refer to Seat Cushion Replacement - Rear in Seats.



Install the fuel injector sight shield (1) to the engine.
Install the fuel injector sight shield nuts (2). Tighten
Tighten the nuts to 3 N·m (27 lb in).


--------------------------------------------------------------------------------
Document ID# 591099
2000 Cadillac DeVille

[alanfeldkamp]

Thanks. I was hoping that it would be simpler than the sender but understand that is most likely the problem. Is there a diagram of all of that you described or is info available online some where? How hard is it to get to the sender?

[Caddyshack100]

Actually, between the paragraphs are supposed to be pictures, but I cannot figure out how to copy them, they are a 'Tiff' format, Tagged information File Format. You seem to have one thing going for you though, (I never thought I would say this) but Cadillac seems to have picked up a good tip from the Japanese, you can get at your fuel pump and sender unit, from the trunk, at least you don't have to drop the tank. A much better idea. Good luck.

[alanfeldkamp]

Roger--Thanks caddyshack100