Hello all. Weird issue today. Out driving today and engine stumbled and shut off. Long story short, ran out of gas and the fuel gauge read 1/4 tank! Never done that before. Is there a recalibrate for the fuel gauge? I'm afraid of a repeat. Don't know what caused it. Had the cluster rebuilt by U.S.speedo about 2 years ago with led and upgraded steppers, new pump/sending unit, new fuel tank and new fuel filler pipe assembly and fuel filter all within last 2 years. Runs great otherwise. Can it be recalibrated or anything to check without dropping the tank? 2003 LTZ swb
Got stranded
- Thread starter Stuntmanmike1977
- Start date
Mike534x
Member
- Apr 9, 2012
- 934
I know you can re-calibrate the gauges on the cluster, but removing them and reseating them in their proper order. But if it read 1/4 , and you were actually on "E" then I would assume that the sending unit is going bad. What pump did you end up putting in there? and does it read correctly when the tank is topped off?
Same thing happened to my 2003 on Christmas day. Gage said 1/4 tank. I haven't had a chance to mess with it.
Mooseman
Moderator
If you didn't get a warning saying you're low fuel, it's likely the float sensor in the tank. If you did, then it could be the stepper motor or the needle is out of place. The low fuel warning will work off the reading from the tank regardless of what the gauge says.
When you filled it, did it go to F?
When you filled it, did it go to F?
pull the fuel pump relay and do a resistance measure on the pins at the socket that go towards the fuel pump. You should get some reading, not zero ("short") and not really high (open). That will tell you if you have connection thru to the pump AND that the pump is "electrically there".
If you have a Tech2, you can read the fuel level in a percentage. If its reading empty, and the guage is not, than you know its the needles. But as @Mooseman said, the low fuel warning would have turned on.
If its reading a percentage, but the tank is empty, than the sending unit, or float, is faulty.
If its reading a percentage, but the tank is empty, than the sending unit, or float, is faulty.
Don't know how to do that, not tech savvy and my meter is 20 years old. Would that cause inaccurate fuel level readings on the gauge? And is there any way to reset the cluster? Can not drop the tank.
When the Engine is OFF... Key OFF and taken OUT of the Ignition... Where does the Fuel Gauge Needle Come to REST on the IPC (Instrument Panel Cluster) Gauge Background? Take an image of what is there to see and Post it back here for us to compare against others.
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sorry I was thinking more about how to check if the pump is working. There is a similar test to determine the continuity to the fuel level section of the pump. I haven't looked at the schematics but there should be a place to do a similar test. without dropping the tank.
ADDED: I quick look and see shows that there is a way to measure the sensor. The spec is 250 ohms full and 40 ohms empty. The "bad part" is that the access is at the PCM connector. You need to disconnect the connector and CAREFULLY probe two pins on the connector at the cable with a multimeter.... carefully, means using small wires / pins to not "injury" the pins in question. The pins are on C1 8 and 22 according to my reference. If your readings are good, that would likely mean your problem is at the instrument cluster.... maybe although I guess your PCM could have a problem in that area without impacting other operations of the PCM.
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Sqrly
Member
This is very helpful information for me as I need to drop my tank and replace the inlet. Do you know how much fuel is in the tank when the low warning light comes on?
My light comes on during pre start but I haven't had the vehicle long enough to even use one tank of gas. I was planning to put 3 gallons in a 5 gallon can and strap it in the back in case I run it too low.
