I'm running a 305 carbed set up and I've noticed that when I crank on the car tons of little air bubbles rush through the fuel filter.

Is this normal? The car doesn't have any of the evap equipment that's how it came when I bought it. I'm wondering if the bubbles have anything to do with me getting hardstarts lately.

Also ive noticed when I open the fuel cap i get really loud hissing coming from the cap.. Well it's noticeably louder than my other thirdgens

What causes bubbles in my fuel filter? Could I have a leak somewhere? Can it be related to my hard starts?

Thanks for any info.

 

chances are excellent that theres a pin hole leak, or suction air leak in a fuel line that allows the pump to suck air, if the leak was on the pressure side of the it would be dripping of spraying a fine mist of fuel, in most cases, Id start by taking the current fuel pump out and inspecting it and its connections and looking for a loose connection or bad hose
think of this logically, if you get a fitting that fits the inlet or supply side of the fuel pump and connect it to a 6-8 foot section of fuel line then hold the fuel line into a gallon fuel tank/gas can thats full of fuel and use that as a test and the fuel filter still shows air bubbles its very likely the pumps defective, if it cures the problem you know its air leak source is located between the tank and pump.
as always isolate then test each individual component in a logical progression

http://forum.grumpysperformance.com/...php?f=55&t=211