Will a fuel injected sending unit work for my 4bbl carb 305?
The units on rock auto (image below) all seem to be for fuel injected setups and i haven't been able to find if the same unit will work on my car.

Any help is appreciated. I'v tried the search function but haven't found a yes or no.

its an 87 5sp Trans am that's been stored for 20 years. Its running but the fuel tank is still sending sludge to my inline filter and my fuel gauge isn't working. I'm buying a new tank and sending unit but unsure of part compatibility. I'v replaced the fuel pump on the side of the block if that's any sort of necessary info.

 

Fuel gauges all work on the same resistance values so the gauge part of the sending unit would be compatible. I'd test the dash gauge first with a simple test, unplug the wire at the sending unit and turn the key on. With the wire unplugged gauge should go past full, ground the wire the gauge should read empty. Resistance is usually 0-100 ohms, you can also check the wire from the gauge with a test light connected to ground should light the bulb dim and the gauge should react.

 

I have no direct experience with this as I am into 1987 to 1992 Firebird Formulas and GTAs with TPI.

Some years of L69 5.0L H.O. V8 equipped Camaros and Firebirds came with a 3 PSI in tank electric "Helper" fuel pump and a mechanical fuel pump mounted on the block. Some L69 & LG4 cars that didn't come from the factory equipped this way were retrofitted at the dealer this way to try to help cure fuel boiling (Vapor Lock) problems later on.

It's my understanding that all 1987 LG4 cars came from the factory equipped this way.

I don't know if you can get the hanger/sending unit for the mechanical fuel pump cars or the ones with the mechanical fuel pump and the electric 3PSI in tank "Helper" fuel pump anymore.

You might have to get the fuel injection gas tank, the fuel injection hanger/sending unit, the DELPHI FE0115 TBI in tank electric fuel pump, and run a fuel pressure regulator to bring the 12 PSI down to the 6.5 PSI for your Q-jet carburetor. You are also going to need some way to power the electric fuel pump. I don't know how things were setup for powering the helper fuel pump in 1987 LG4 cars.

Hopefully someone who knows these 1987 LG4 cars can chime in. Maybe someone with the factory service manual for 1987 can help.

 

This question is asked every few days. Gotta be one of the most popular ones here. Should be a sticky IMO to keep from cluttering up the forum with the SAME DAMN QUESTION being asked over and over and over and over and over, butt that's not my decision to make.

Unfortunately, parts for anything carb related in stock vehicles, is getting hard to come by. No surprise that you can't find one to just buy, since no one else can either, because they aren't being made anymore, and haven't been for a VERY long time now (at least 10 years, maybe more, ALOT more).

A bit of reading before posting would help. You'd see what other people have done to overcome this ... simple ... opportunity for a solution. It's really not that hard. In a word it involves using an EFI one, dispensing with the pump (or buying one without that, aka "module"), extending the line that the pump would feed down into the tank, and mounting some sort of filter at the end where it picks up the fuel. Eeeeeezzzzzzzyest way to do it is probably a short stick of brake line and a compression fitting, and maybe one of those little bronze carb-inlet fuel filters. The "sock" filter that was used on those from the factory is one of the parts that has disappeared without an exact replacement, and old stock ones are largely crumbling to dust nowadays anyway. Unleash your inner creativity on it.

 

https://www.ebay.com/itm/255841740250
Here's one if you want to spend the coin. I would be doing what Sofakingdom suggested. A new FI unit some brake tubing and adapting a sock to the bottom like the factory unit. As long as the unit fits the hole in the tank a little engineering and you're good to go.

 

the 87 LG4 should have a fuel pump in the tank as a helper for the block mounted pump anyway

3 wire connector

 

You're correct naf! I ended up ordering the ebay part from Beeman's link but after removing the sending unit, there was a fuel pump strapped in...

I went with Delphi Fuel Pump Hanger Assembly (Part Number: 4664-05931944. edit*SKU HP10266*) from PartsGeek - it comes with the helper pump in the box for half the cost of the ebay unit. Fingers remain crossed.

 

Fingers crossed is what you will need if you try to run that DELPHI HP10266 fuel pump module assembly on your carbureted engine.

That part is for the 1985 to 1989 2.8L V6 and the 1990 to 1992 3.1L V6 fuel injected engines.

The 22 GPH/83 LPH flow rate should be fine for a stock LG4, but the system pressure is 44 PSI.

Your Q-jet will want the fuel pressure to be in the 6 to 7 PSI range. 44 PSI will overwhelm the block mounted mechanical fuel pump, and the needle and seat assembly in your Q-jet.

 

you're correct Airwolfe. I had to remove the mechanical pump no the side of the block and run a regulator to get down to the correct pressure. Everything is 'running' fine but the fuel gauge is still stuck at 3/4 full... so next step is tracing wires.
Its possible that its the cluster itself.

 

Well, I'm glad you caught it before something bad happened like the Q-jet puking gas all over a hot engine and catching the car on fire.

Did you have to cut off the fitting on the fuel supply line on the fuel pump module to fit your rubber fuel supply hose on the car and did you have to extend the wiring from the fuel pump module to connect to the fuel pump wiring harness on the car?