1992 Z28 5.7 80k miles
I haven't driven it in a couple months. Its 70 degrees, I start it up, and it feels like 1 cylinder is missing. After about a minute, it goes away.
So its not a huge problem, not enough I want to go dig around and diagnose if I don't drive it much anyway. But was curious if anyone might throw out an idea or two of what it could be.

 

Puffing blue smoke on start up too? Could be valve seals leaking oil in, causing a cold misfire till the oil burns off. Checking plugs will tell you more.

 

Oh good one. I don't think I saw any smoke though. I can do a compression test next spring though.

 

Valve seals, not valve seats. A compression test will tell you nothing about valve seals. Not saying that you shouldn't do a compression test, it may provide valuable information but it won't tell you anything about the valve seals.

 

How has it started up and run since that initial start-up? If it's been ok with each subsequent start up, then it was probably just gummy injectors from having been sitting idle for so long.

There was a time, years, when I had zero time for my Formula, and it would sit for several months at a time without being started. Then when I'd eventually start it, man, it was rough, but would smooth out as it continued to idle. After a about three episodes like that, I decided to try pouring a bottle of Techron into the tank about 24 hours before I planned to start it and take it for a drive. Then that next day, it would fire right up and run beautifully.

 

Just think..when you get out of bed do you jump up and move quickly?? guessing no lol...shes just sleepy and trying to get started after sleeping!!!


Seriously though, prolly just sticky injector or maybe condensation in the cap or something.



Maybe a good tune up if you never did one.