EDIT: new questions and clarification. Hopefully this will help you help me.

What: Ok so my corvette has some problems running lately, regardless of rain.

Problem: Progressively gets more and more grumblish/sluggish. Seems the engine is firing and I'm not picking up any speed, or that it's misfiring. ie. Today I woke up and dropped off some books at the library, on the way over, it was GREAT. on the way back, I noticed it would start missing(notice this during certain parts of acceleration and when idling it becomes really rough). Then 5minutes after I got home I left to pick up my check, and it became quite rough. When accelerating it would seem to intermittenly grumble, then catch for a bit, etc

What I know: The coolant leaks. I put in new coolant Monday, and it is already down about a quarter inch on the reserve.
It blows smoke out the back after I start it up and it's been sitting for a while. ie: this morning it blew smoke up, then ran great for first 5minutes. the 2 second times I started it up there wasn't much if any smoke going out the back, but it ran a lot worse.
Also to note a hose to the reserve blew about a month ago, but my dad repaired.

Guesses: Maybe the coolant leaks somewhere into the head gaskets? I'm really stumped. My dad thinks it's electrical/fuel injection, but because it seems to get progressively worse as it 'warms up' and it has these problems regardless of rain, I tend to think it is not.

 

Sounds like your gas tank cap / neck might be leaking, allowing water into it.

 

EDIT: see top

 

Keep an eye on your coolant level, getting that low and "gurgling" isn't good. Start the engine and let it warm up and watch the overflow tank, if you see the inlet tube to it blowing bubbles in the tank...blown head gasket. Also, smell the exhaust when running...does it smell like coolant?

 

There is a little drain plug in your gas cap compartment, it is very possible that is clogged and will not let water drain out. This happened to mine and after a heavy rain, water would seep into my tank. I just took a garden hose and flushed the drain tube clear. And i may be crazy but check your ignition system too.

 

Shameless bump(is this allowed?)

 

hey check ur valve covers see if the bolts need to be tightened up or your heads could be going bad as for the coolant prolly a bad water pump or sumting but the other guys opinions were good too hope it works it

 

Start with a pressure test on your cooling system. The smoke on start up may be coolant, or it could be just the valve seals not doing their job.
What shape is the cat. A plugged up cat can cause similar symptoms with performance.

 

Wow, just saw how old this thread is. Looks like newbie is diggin up the dead