low fuel light

[jeffbentleyreich]

I ran out of fuel on the freeway several weeks back and the dealer told me the low fuel regulator was bad and could be replaced for appx. $800. I said I didn't need it... Is that correct - $800. to drop the tank and replace some sending unit???

[More Power]

Does your fuel gauge read more or less accurately?

The sender in the fuel tank is read by the vehicle ECM, which then sends data to the instrument cluster fuel gauge. The ECM also enables the "Low Fuel" warning if the fuel is below a prescribed level.

MP

[jeffbentleyreich]

The sender in the fuel tank sounds like the part that is bad but my fuel guage does seem to read fairly accurate.

[More Power]

The ECM monitors the sender in the fuel tank, interprets the information, then sends a signal to the instrument panel fuel gauge. The ECM activates the "Low Fuel" warning when a low limit in percent of remaining fuel is reached (I read the value somewhere, but can't locate it just now).

If the correct fuel level is being seen by the ECM and/or Tech II scan tool, the sender must be working properly. Page 8-776 of the 2001 Service manual outlines the test procedure for the fuel tank sender, and guides the technician through a process of testing the related components in the system.

In addition, a Tech II scan tool can also read the level of the fuel (through the sender) as a percentage - in the "Engine Data Fuel System" display.

What I'm saying here is that "if" the sender is "sending" correctly, it cannot be at fault. It doesn't have a low fuel switch in it. The sender simply sends a resistive value to the ECM, from 40 to 250 ohms. The ECM makes all the decisions about whether to activate the Low Fuel warning.

MP

[Stage1]

On 03' CC long bed I just turned on the low fuel light w/ needle in the red empty part of the guage, finally found fuel and it took 31.6 gals :eek: This was not a test!

Les

[jeffbentleyreich]

Thanks for the info MP