Fuel Gauge - Sender -Wiring

robsawatsky · February 25, 2003

Fuel gauge started acting up a couple of days ago. Checked posts here but didn't see these exact symptoms. Any suggestions?

Fuel gauge started by slowly drifting around the correct reading (usually upwards). Then today it did that plus swinging all the way to E. Actual reading should be a bit below 1/2 tank at the moment.

Thanks

CMNTMXR81 · February 25, 2003

http://www.gm-trucks.com/cgi-bin/ib3/ikonb...=ST;f=1;t=15949

robsawatsky · February 26, 2003

Well, it looks like it is probably the sender. After, filling up, the gauge reads fine at full. This after, getting flakey, bouncing around at about 1/3 tank and then going to E at about 1/4 tank.

CMNTMXR81 · February 26, 2003

Would you like the process for replacing the sender?

bcfitzsimons · February 26, 2003

CMNT-would you mind posting the process? My fuel gauge does the same thing. If it's an easy fix, then I'll try it this weekend. Thanks-Fitz.

CMNTMXR81 · February 26, 2003

It involves removing the fuel tank. Do you still want it?

robsawatsky · February 26, 2003

I'm interested in the process, but not happy about it because I thought before hand it would involve removal of the tank and confirmed it last night when crawling around underneath to see if there was a wiring problem.

Well, you can't even really check for a wiring problem based upon the sender connector is while nigh unaccessible unless you have thin multi-jointed arms and a flexible viewing scope. But, it sure did confirm the tank has got to come out, or cut a hole in the bed : )

CMNTMXR81 · February 26, 2003

Here you go. You mean to tell me you don't have rubber band arms.

Fuel Tank Pressure Sensor Replacement Exc Utility
Removal Procedure

Caution

Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

1) Disconnect the negative battery cable.

2) Relieve the fuel pressure. Refer to Fuel Pressure Relief Procedure .

3) Drain the fuel tank. Refer to Fuel Tank Draining Procedure .

4) Remove the fuel tank. Refer to Fuel Tank Replacement .

5) Disconnect the fuel tank pressure sensor electrical connector.

6) Remove the fuel tank pressure sensor (1) from the fuel sender assembly (2).

Installation Procedure

1) Install the fuel tank pressure sensor (1) on the fuel sender assembly (2).

2) Connect the fuel tank pressure sensor electrical connector.

3) Install the fuel tank. Refer to Fuel Tank Replacement .

4) Refill the fuel tank.

5) Connect the negative battery cable.

6) Install the fuel filler cap.

7) Inspect for leaks.

-Turn ON the ignition for 2 seconds.

-Turn OFF the ignition for 10 seconds.

-Turn ON the ignition.

-Inspect for fuel leaks.

Other steps mentioned

Fuel Pressure Relief Procedure
Tools Required

J 34730-1A Fuel Pressure Gauge

Caution

Remove the fuel tank cap and relieve the fuel system pressure before servicing the fuel system in order to reduce the risk of personal injury. After you relieve the fuel system pressure, a small amount of fuel may be released when servicing the fuel lines, the fuel injection pump, or the connections. In order to reduce the risk of personal injury, cover the fuel system components with a shop towel before disconnection. This will catch any fuel that may leak out. Place the towel in an approved container when the disconnection is complete.

Caution

Before servicing any electrical component, the ignition key must be in the OFF or LOCK position and all electrical loads must be OFF, unless instructed otherwise in these procedures. If a tool or equipment could easily come in contact with a live exposed electrical terminal, also disconnect the negative battery cable. Failure to follow these precautions may cause personal injury and/or damage to the vehicle or its components.

1) Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental attempt is made to start the engine.

2) Loosen the fuel filler cap in order to relieve the tank vapor pressure.

3) Connect the J 34730-1A fuel pressure gauge or the equivalent to the fuel pressure connection.

4) Wrap a shop towel around the fitting while connecting the gauge in order to avoid spillage.

5) Install the bleed hose of the gauge into an approved container.

6) Open the valve on the gauge in order to bleed the system pressure. The fuel connections are now safe for servicing.

7) Drain any fuel remaining in the gauge into an approved container.

Fuel Tank Draining Procedure

Caution

Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.

1) Remove the fuel fill cap.

2) Use a hand operated pump device in order to remove the fuel through the fuel filler pipe.

The procedure for dropping the tank if you need them depends on what cab style you have.

bcfitzsimons · February 27, 2003

Sounds like a breeze.

Maybe I'll just live with it and fill the tank up every 200 miles. Sounds easier, anyway. With my luck one of my buddies will pull into the driveway with a lit cigarette just as I'm draining the fuel tank .

Fitz.

timk49 · February 28, 2003

The mechanics at work replaced the puel pump in two vehicles last week. One was in a 2500 flatbed truck. All went well it works fine.

The other was in an S 10 the fuel pump works fine but the gas gage is pegged on E. ( now the service engine soon light is on) what now?

The fuel pump for the 2500 and the S 10 looked the same but there was $ 150.00 difference in price.

CMNTMXR81 · February 28, 2003

The fuel pump on my friend's 2001 Nissan Maxima looks nearly identical to ours too! What makes the main difference is how much it can pump per hour.

What year, engine, and other important info is the S-10?

HD Dave · April 30, 2003

Fuel gauge started acting up a couple of days ago. Checked posts here but didn't see these exact symptoms. Any suggestions?

Fuel gauge started by slowly drifting around the correct reading (usually upwards). Then today it did that plus swinging all the way to E. Actual reading should be a bit below 1/2 tank at the moment.

Thanks

Just another option to make this job a little easier.... I recently replaced the fuel pump/sending unit on my old '99 K2500 (just traded it for a new 2500HD!) and did it quickly and easily by disconnecting the tail light harness near the back bumper and lifting the bed off of the truck. Several of my riding buddies work for the local Chevy dealership and said that this was a much easier way of replacing the unit. Plus, you do not have to drain the tank using this method. Remove the screws that hold the filler neck (behind gas cap door) to the body, disconnect the grounding wire and then remove the bolts that secure the bed to the frame (six or eight of them) and lift the bed up and walk it back about three feet to set the front of the bed on top of the rear tires. I used my engine hoist to support the rear of the bed to keep it even with the front of the bed. You could also do this under a big tree limb with a "come along" if you do not have a hoist. I had a couple of neighbors lend me a hand lifting the bed(bribed them with cold ones!) and I had this job finished in less than an hour. It's MUCH easier than draining and dropping the tank itself.

I hope this helps!

Dave