5KTQ gas cap question--C.C.

[Ameer Antar]

>A recently acquired 5kcdtq did this and the cap would almost shoot out of
>your hand especially when the tank got low.  When I rebuilt the fuel system
>it went away.  This car had an after-market fuel pump that wasn't installed
>correctly and the check valve wasn't working, the filter had never been
>changed and the accumulator was shot.

If you only changed these items, I don't see the connection. These items 
are designed to only allow fuel to pass through it. The only thing that 
allows vapor to pass is the vent line which leads to the charcoal 
cannister. I just don't think someone who has pressure buildup in their 
tank will cure their problem by replacing the accumm. or check valves...

I don't have a CC freq valve, but I think there is some sort of related 
valve on the intake boot. I assume that the valve directs the gas tank vent 
line into the intake manifold when the car is on and under vacuum. When the 
car is off and under boost the vent must go to the CC. Correct? Is it 
dangerous to have an old CC?

I wish there was a better solution to the CC, but I can't think of any nice 
ones. The thing is the CC is really a maintenance item. After a few years 
the effectiveness of the charcoal decreases as it probably gets covered w/ 
muck, and it will prolly be all used up.

I've never heard much talk about these things, and mechanics usually never 
even touch em. If it's an emissions issue [gas vapor escaping], why is that 
these items are very rarely replaced or checked? Also why do we have to pay 
$75+ for a plastic container w/ charcoal in it? Oxygen sensors are much 
more complicated and they've already standardized those. Universal ones are 
$15-20. Cat converters are similar, but differ in how they connect to the 
car, just as in o2 sensors...They could do the same here and increase the 
amount of people changing their CC's. Since it doesn't really affect power 
or economy, owners aren't gonna shell out that kind of cash just b/c they 
found out their cc doesn't meet emissions standards. Just my thoughts...

-ameer