Fuel sending units

[Ron Sebastian]

Ron I'm not trying to be difficult when I say this but I was simply answering your question which was "The solenoid grounds by being bolted to the frame. Is this correct on an 87" I gave you the answer to that nothing more.

IDK, if you have a ground issue or a power issue. The only way you will solve your problem is though continued troubleshooting. At this point I'm not really sure I can offer more suggests than what I and others have made, but I'm certainly able to answer questions that might help you troubleshoot it.

I will look over the thread again and see if I can come up with any good ideas.

Sir, I appreciate the help. The reason I think it's a short is the gas gauge reads full when I know it's not. If it were a ground problem the gauge would read empty. Am I wrong with that? Also the truck runs on both sides when I switch tanks. Ran out of gas in the left tank yesterday and switched to the right tank, fuel gauge didn't move but the truck ran fine. I am narrowing the problem down to that, somewhere from the tank switch valve to the gauge the wire is shorting.

 

[greatlakes08]

I just installed a new sending unit and fuel pump on my suburban. Make sure the sending unit you get is calibrated for the correct tank size you have otherwise it won't read correctly on your gauge. I purchased my sending unit from Oreillys (Precision Brand) and I purchased my pump from Autozone (Delphi Brand). When I compared the pics of the fuel pumps available Delphi seemed to look almost identical to the AC Delco. I would of purchased the Delco but no one had it in stock and didn't want to wait for shipping.

 

[gmbellew]

I just installed a new sending unit and fuel pump on my suburban. Make sure the sending unit you get is calibrated for the correct tank size you have otherwise it won't read correctly on your gauge. I purchased my sending unit from Oreillys (Precision Brand) and I purchased my pump from Autozone (Delphi Brand). When I compared the pics of the fuel pumps available Delphi seemed to look almost identical to the AC Delco. I would of purchased the Delco but no one had it in stock and didn't want to wait for shipping.

curious if the float/sending unit needed to have any calibration period?

I just had a shop replace the same on my 1990 suburban. the gage reads full at full, right at full line. the old sending unit would read almost a quarter past full at a full tank (as did most other squarebodies i have driven). the new unit drops faster than the old guage, and will show about 1/4 tank at about an actual half tank. and then it slowly, slowly drops from there. so far, i have only ran the tank down about 25gal on the 40gal tank. I am wondering if I need to run the tank down low to get the float to "adjust" on the low end so the gauge will sweep more accurately, even if it reads high when full like all the other trucks.

 

[greatlakes08]

When I ordered my sending unit in description it mentioned the size of my tank. When I looked at other sending units not specific to my vehicle they mention different volumes based on what vehicle they are for. When I pulled the sending unit out that was in my tank I looked up the part number and it was for another GM vehicle and my gauge would always show way over the full mark and then suddenly drop down to half after a while. After installing the new unit it I put 7 gallons in and it showed less than a 1/4 tank. I then filled it up and it went to the full mark correctly. Sorry for the long winded response but overall I believe the factory who makes the sending unit calibrates for the specific tank volume in that vehicle.

 

[SquareRoot]

Sniper will cause you waaay more headaches than this fuel guage issue. Do your research. Ask me how I know.