Paul Setterholm

Purchased car recently from older man who said he was getting too old to drive it. Car had 61k miles. I've been daily driving since I bought it and it gets a hesitation in power. I changed spark plugs, cleaned maf,throttle body, ran spray seafoam through upper intake, fuel injection cleaner in gas tank. I cut air filter lid and added k&n, did the tb coolant bypass. Checked for vacuum leaks and it still does it. I just received a 160 degree thermostat also a low coolant censor and msd plug wires I hope to put in this weekend. The car has a high voltage coil, aftermarket exhaust and the previous owner replaced computer with an upgraded one. His memory is going so he kept a diary on the car and later wrote that he had a corvette specialty shop upgrade the program (Dyno tuned?)
Also, when starting from a dead stop, if you give it too much gas in 1st gear it feels like it "kicks down" into like a passing gear. The cars pulls hard and spins tires when I wasn't trying. I have to feather the gas so it doesn't seem like I am racing. Is this normal? Car has really good power for a L98. More than I was expecting. I'm not a mechanic but can do the basics. Any advice? Thanks in advance

Paul Setterholm

Also I was getting 22.5 mpg before tuning it up. Getting 24 now (according or the digital dash reading)

DanielRicany

This is the first place I would investigate.

jv9999

I'd look at the date code on your tires, they are probably old and hard so they spin easily.

GUSTO14

Well your gas mileage is pretty much where it should be.

Is your overdrive transmission dropping down into low range and up shifting as it should? When you shift into 1st gear it should automatically drop down into low range. When you shift into 2nd at normal acceleration rate it will shift into high range (unless you've turned it off). It should stay there until you hit the throttle hard or slow and drop back into 1st.

I have an 8k mile '85 I bought new.

Good luck... GUSTO

Paul Setterholm

I turned the overdrive off and it runs perfectly. So I was chasing the wrong things. Is there any service related things I can check? Or will I need to bring it to a shop?

Paul Setterholm

The one thing the previous owner didn't provide me with was the owners manual

hcbph

Didn't get one with mine either. Ebay was my friend, likely will be yours too.