So just wanted to share this since I haven't seen anyone do this and I've read plenty of threads watched videos and even dropped the driver's fuel tank for sending unit replacement. After 2003 GM engineers came up with this fabulous location for sending units which conveniently they charge 1k -2k at the Stealership to replace.

I love my 2004 Vette but not that much and dropping one of the tanks is really a pain especially in an automatic.

I know these cars suffer from bad fuel level sending units and codes and erratic behavior of the fuel gauge. Techron and seafoam may work but if you have to go in there because it doesn't this may be worth a try.

You have to be very very very careful especially where the cross beam meets the tub of the hatch the tank is sometimes less than 1/4" away.

The great thing about this is once you do it to both sides you can access the units in a matter if minutes.

When cutting i used old scap plates of steel as a barrier between the cut and the tank.

Use a 4" cutting disc angle grinder for 90% of the cuts carefully. Use 1/8" drill bit to weaken the joint then finish with a oscillating tool to remove the panel.

Don't cut yourself like I did be careful with sharp edges and wear your PPE and have means of extinguishing nearby.

I will be fabricating a cover plate in galvanized steel that will be covering the area with 8 threaded bolts and structural adhesive.



The main reason this was done was to correct a P0268 code and a dancing fuel gauge.

This was inspired by many foreign vehicles that are designed to have access panels in the body for sending unit service. {Not like the folks at GM}

Happy Thanksgiving 🦃

 

I say more power to you!
I can’t name one off hand, but I’ve read of more than one car having an access panel for the fuel pump from the factory. The only reason GM doesn’t design it that way is that they plan and design the fuel system to survive through the warranty. After the warranty, they are quite happy to sell parts and — to some degree — labor.

 

I would do the same thing. The F body guys do.

My 04 Monte Carlo SS had a factory access panel in the trunk for the fuel pump. I think all of those W bodies did.

 

I've been struggling thinking about whether or not I should grind an access door in the floor of my 2000 vert to access the upper Ebrake cables, as it appears theres no way to reach them without dropping the cradle. The carpeting would easily cover it, and nobody except me would know it existed. Sorry if this is a hijack. I say congrats on saving a LOT of $$$$......

 

I think there is value in sharing any idea that can help others out. Feel free to share your progress I hope I inspired you. Be very careful. I'll share some additional pics of what caused the code issue and my strategy to remediate the problem without buying a new sending unit.

 

More pics. So the code issue is driven by damaged brushes on the sensing unit. My solution cost zero dollars to fix. It involved trimming the other brush bending them down further so that the shorter brushes now touch and curling the tips for a smooth glide. With the shorter brushes I noticed they would be out of range if the tank was full so I placed a little stopper so that the float arm would drain before the brushes were out of range on the upper side. On the empty range they had the opposite problem because they don't reach the lowest point but it doesn't affect the reading much. I went ahead and also created the access panel on the driver's side. So far so good 👍 I'll report back if there's any issues.

Enjoy..

 

I'm thankful my 03Z has pumps on the bottom. If I had the later fuel system, this MAY have been on my list to do.

How did you know where to locate the cuts?

 

There's a couple profiles on the hatch deck that I followed and then the other area by the beam I kinda figured based on what I saw through the passenger side wheel well inspection hole.

 

So i was getting this code and it looks like the sending but on the driver's side went out. If your on a budget swap the brush part with a "Fuel Gas Tank Level Sensor Pump Mounted NEW for Buick Chevy GMC Isuzu Saab" Dorman 911-014.

I didn't measure the resistance on the board but it may be the same if you want to put the whole unit in. Keep you sane float and arm.

 

Sure you have that Dorman number right?

 

Yes, just take the plastic that pivots with the brushes. Keep your board and lever.

The one I got was not a dorman brand and it was under 20 bucks

 

I had a different problem but the same recommendation: "Drop the fuel tanks and put in a new pump." I was getting my car tuned and the tuner said I was getting too lean at WOT. He recommended a new fuel pump. I did some research and installed a "Boost-A-Pump" instead. That gave the fuel pump more voltage only at WOT, and cured the too-lean condition.
If I ever have to actually replace the fuel pump, your method - which eliminates fooling with crossover pipes and the passenger side tank - will be my first choice!
(I'm a little surprised that no purists have chimed in that you have ruined the originality of your Corvette by cutting a hole in the trunk floor! Based on a Forum post, I cut a hole in my cowl to change my oil pressure sensor and the weeping and wailing was significant! I saved a lot of time though! )

 

Great man. My goal was to keep it simple and provide a solution to a problem. I'm not trying to keep the car as perfect as these engineers created it. The goal is you gotta make it work for you without busting the wallet or your time.

 

It's your car to destroy in whatever way that you see fit. I have changed my tune on the hack method. Not only does it not bother me anymore, I flat out encourage it! Post video of those hole saws and oscillating tools in action !

 

Rconce

Excellent work. Do you think you might be able to provide a templet and some measurements for both sides of the access ports? That would be awesome!!!

My 04 Coupe has not had a working fuel gauge in over a decade. Last time I talked to someone about fixing it price was $2200.

My car is not going anywhere so I really don't care about some sort of resale issue with making the cuts.

Incidentally, my 1979 280zx has an access panel for the fuel sender right there in the middle of the floor with a nice o ring seal.

Thanks

VERYSOON

 

Absent a template, You can use the circles and lines cast into the fiberglass as a guide (Based on the pictures in this thread). You don't need precision, just careful shallow cutting to do it. When you're done, you can glass it back together. If I ever have to replace the pump, that's what I'll do, since I got the same estimate as you to drop both tanks and replace the pump/sending unit.

 

Thanks helphos
I screen shot all the pics. Will probably do this next few months. It would be nice to have a fuel gauge that works as well as the one on my 69 Vette.

VS

 

Good idea! This forum has saved me lots of money! When my fuel gage went on the fritz i was able to get it working again with a couple of Techron treatments. If you haven't ried it, you should!
My son cut a flap in the sheet metal trunk of his camaro to replace his fuel pump. Very easy repair versus what the dealer would do. So I have no problem cutting the fiberglass in the trunk if my fuel pump finally gives up. I'll just glass it over when I'm done. Good for another 20 years!

 

I know I'm bumping an old thread, but I just wanted to share my appreciation to the OP. I just installed an A&A kit and shortly after the BAP install I had some no start issues that all lead back the the OEM fuel pump failing. My thoughts were the BAP extra voltage just helped expedite it's already inevitable end. I had no desire to pay that much for a fuel pump swap and was wondering if anyone had cut a panel like people (myself included) have done on other models. Most all the posts I found on the net were about C6's. This was the best, and almost only, documented post on how to do this, and is going to save me a ton tomorrow when I cut out the old one and install the new DW400.

@Rconce01 Thanks for this post!