I wrapped up a project on my car back in November, replacing the interior as well as installing some insulation to help with interior noise. Boy what a difference it made! You used to have to yell to be able to hear each other when driving on the freeway; now it’s still not as quiet as an economy car, but you can at least have a conversation at a normal level.
Today I tackled another common C5 problem: a plugged jet siphon pump in the passenger side fuel tank. The corvette has an interesting fuel system. There are actually two tanks, connected by a crossover pipe at the top (to transfer fuel to the second tank during fueling.) The passenger side tank drains first, followed by the driver’s side. This is accomplished by an electric pump on the driver’s side, and a mechanical venturi pump on the passenger’s.
The problem is the orifice on the passenger’s pump is tiny. I mean head of a pin small, and this can easily (and frequently does) become clogged with debris. When the car detects that the driver’s side tank is more than 1 gallon lower than the passenger’s side tank (which should never happen if the pump is working correctly) it will peg the fuel gauge to empty and throw a P1431 code. Today I tried unclogging the pump instead of replacing the whole unit.
The gas tank is tucked in behind the rear passenger tire. It’s not terrible to access, but you do have to remove the inner wheel well, as well as some additional paneling. Of course, with the pump not working, the gas tank is holding around 8 gallons of fuel. There’s not much clearance under the car without access to a lift, but I was able to get all of the gas out. Please don’t try this at home.
Here’s the pump itself. I was able to remove the obstruction from the orifice using a very small sewing needle. The two screens to the sides are supposed to keep out sediment, but with how small the hole is in the pump the filters are pretty much useless. There’s another version of this assembly that comes inside of a cotton sock that acts as a fine filter, and if I continue to have trouble from this one I’ll probably swap over to that.
While I had everything apart, I decided to try and knock some of the road noise out of the wheel wells. The trunk sits right above here, and connects directly to the cab inside. The plastic beauty panels themselves turn the wheel well into an echo chamber, and amplify the noise coming off the wheels. I bought some Peel & Seal to line the inside of the beauty panel, as well as the exterior of the tub of the trunk. The dense rubber should dampen the majority of vibrations. NOTE: Do not use this as soundproofing inside a car. The rubber itself is a carcinogen, and also smells awful.
The shiny aluminum is hidden behind the plastic beauty cover once reinstalled. I went ahead and did both sides, but here’s a comparison before and after.