Write-Up: Fuel Pump/Tank Sending Unit Replacement

Rickw wrote:

dscott2000 wrote:

dreww wrote:

does replacing the fuel pump require actually dropping the tank on these cars?
I did a search and couldnt find an answer here. I thought we had a write up on it. I just figured it would be the hard way on our cars, like everything else (belts,etc.).

Yes, you do.. I just had to replace the fuel pump in my friend's 97 S/C and it is located in the gas tank. It is a HUGE pain! But, after its done, it is well worth it.

dscott2000, There is an access panel in the trunk that allows for easy removal of pump without dropping the fuel tank.

I guess I owe someone an apology.. I didnt even look for the access panel. I just dropped the tank. I didnt think for a second that GM put in the access panels in. Sorry for the confusion.

The 1998/1999 fuel tank sending unit is a different part number than the 1997 but the wiring schematic shows it to be functionally the same. So I took a chance and ordered a '98/99 unit from ebay since it was too cheap to pass up. I ordered from this guy: http://stores.ebay.ca/evalero1 and I figure I saved over $100 on the parts. The job itself took about an hour and a half, there was a lot of corrosion on the ring holding the pump assembly in the fuel tank so I also cleaned that up at the same time.

Here's the original unit. Once I pulled it out, I could see the contacts were worn right off the rheostat. You probably can't tell in this crappy phone picture though.


The difference in the two units was the wiring harness, the actual rheostat modules looked to be pretty much the same:


All I had to do was to de-pin the old and the new sending units, and re-pin the new one into the old harness. Just insert a very small jeweller's screwdriver or piece of stiff wire in the notch above or below the purple wires and pull the wire out of the connector.


You should probably change the sock on the fuel pump while it's out but I was irritated after laying in the trunk so I skipped it. I tested it out of the tank before I re-installed. If you do this remember that the gauge will move very slowly, regardless of how fast you move the float. It will actually take a minute or two to go from empty to full. Check for fuel leaks before you re-install the access panel.

What is a resonable price to install fuel pump for a 96 s/c. Taking it in to be replaced and dont want to get hosed. Just a round about estimate. I'm not sure if my model car carries just the fuel pump, or if it has that whole pump sytem that needs replaced. Apreciate your time if you can help out. Thanks

You are having it done somewhere? I'd guess around $400.

does anyone know if the 96 has the easy access panel for the fuel pump in the trunk?

Yep, it does.

It's pretty simple to change, but the rusted o ring can be a pain to get off.

I still need to take mine back out and put it back together again as I'm getting an odor of gas in the car.

I had mine replaced and the shop decided to reuse the old rubber gasket rather than the one supplier because it looked so much different. Bad mistake as it leaked when filled up.

Would it be possible for anyone who knows where this access panel is, to take a picture of it?

It might not be for a week or two but I'll be swapping a pump and sender so I can take a few pics when I do it.

Thanks turtleman! Looking forward to it.

Did you get this sending unit for the Aurora, or is there a Riv specific unit?

If I remember correctly when he bought it the seller had 98-99 Riv.unit for sale.
Also, remember he's in Canada and so is the vendor if that makes any difference to you. Some people don't like buying from Canadian vendors.

Canada? What's that?

Good point, better to get it here in the states if possible. Rock Auto has a fuel level sensor kit for $128 - think I'd rather do business with the Canadians.

Not having much luck here.

Jack the R wrote:

Did you get this sending unit for the Aurora, or is there a Riv specific unit?

Did your sensor go out too? mine did

It's not entirely out but it doesn't read right. It's still useful within the first half tank.

Jack the R wrote:

It's not entirely out but it doesn't read right. It's still useful within the first half tank.

mine fails... it read full and i went and put 17.8 gallons in my tank

So what's the issue with ordering from Canada? VAT tax?

Come to think about it I bought something from a Canadian Vendor last year without any troubles, although the price did include shipping.
The only issue was it seemed to take UPS a long time to get it here.

I contacted the seller. Apparently he's out of Rivi sensors. He suggested trying a Skylark sensor. Wouldn't the Aurora sensor be a better bet? I'd rather not play "try it and see" either way if it's going to involve splicing wires

Jack the R wrote:

I contacted the seller. Apparently he's out of Rivi sensors. He suggested trying a Skylark sensor. Wouldn't the Aurora sensor be a better bet? I'd rather not play "try it and see" either way if it's going to involve splicing wires

I'm going to splice my wire's... and use hot glue to seal them than shrink wrap and electrical tape.. i don't want those exposed!!!

Where did you find a sensor?

Jack the R wrote:

I contacted the seller. Apparently he's out of Rivi sensors. He suggested trying a Skylark sensor. Wouldn't the Aurora sensor be a better bet? I'd rather not play "try it and see" either way if it's going to involve splicing wires

At his prices, try one of each and let us know.
Splicing wires is not a problem at all. Just solder and heat shrink.
There is such little current in there it can't hurt anything or cause problems. If it could your existing worn rheostat would have already gone BOOM.
Just keep the wires covered and separated. Just like they are now.
I'm serious, there is nothing to worry about as far as explosions unless you cause an substantial arc in gasoline vapor.
This, the rheostat and wiring, is always in fluid gasoline.

Can one of the shop manual guys check to see if the Riv and Aurora have the same tank (if it says?)

Jack the R wrote:

Can one of the shop manual guys check to see if the Riv and Aurora have the same tank (if it says?)

Doesn't say Jack, but there are two different sections for Tank Removal depending on which car, Aurora, or Riv. The Illustrative pictures look exactly the same though.