For some background - I've been driving the car for a few days after being stored for around two years. The first day I drove it there were no real problems. But there was a whining noise at idle, and while the revs decrease after revving it, presumably something with the power steering pump. Any info on that would be great but it isn't the biggest problem. Then the next day I drove it, an issue arose where when flooring it, it would hesitate for around 1.5 seconds before unleashing full power.

The next day (today) the car drove fine at first, with no hesitation. Now I don't know if that is related to the issue I have today, as now when I went to give it full throttle, it was pretty much unresponsive and the exhaust sounded almost clogged and muddled and not loud and aggressive. Out of instincts, I took my foot off the gas right away, and when I tried brute-forcing and keeping my foot on the gas, it was no help. Any information will be a great help.

 

Need to know year, trans. If sitting very long did you drain old fuel before starting. If not you could have old bad gas that’s clogging up your fuel filter & injectors.

 

1985, auto transmission. It didn't have much fuel in it while in storage and I filled it with super from a reputable gas station. The car drove fine before it was put into storage, so what could occur in the span of a few hours of driving to make it bog like that? Currently going to get the cat gutted out (most likely going to get a high flow cat within the near future). Thanks for the reply again!

 

Do you have or have access to a Scanner or OBD1 Code reader? This would be the best way of diagnosing any problems.

Pull your Oxygen sensor out and see what happens to your exhaust, if your catalytic converter is plugged it will push a lot of air out of the O2 bung. I left a car sit for about six weeks and when I got back the cat was plugged. With a Catalytic converter plugged my car would start and idle, it would not go very past idle before coughing and going back to idle.

The Oxygen sensor is designed to last 2 years or 50k miles. I would replace it if it is over 24 months old. The MAF sensor might be causing you issues. A faulty MAF will make the car stumble and not rev either as it can send erroneous data to the computer. They can be cleaned sometimes with a special MAF cleaner spray but be careful as the sensor is a tiny wire about 1/10th the thickness of a human hair and can break very easily if you are not careful.

For a car that sat a while I would probably add a Bottle of B&G 44K Fuel Injection System Cleaner to clean the system out. Todays gasoline only has a shelf life of about 30 days so anytime your Corvette is going to lie dormant be sure to add fuel stabilizer that neutralizes the Ethanol.

Do a basic tune up and verify that everything is working properly, I suspect that the problem will show itself more clearly.