93 cranks over but won’t start
 

hi, new to this site and to owning a Vette. I just bought a 93 40th anniversary edition. The car had a little miss in it that I noticed on the way home after buying it. I changed the plugs and noticed that one plug looked new. After changing it,I tested the cylinder that wasn’t firing , and all was good and she cranked right up . So I changed the remaining 3 plugs , and was ready to go for a ride but now the car only cranks over (rough) no fire. My question is , can this be a security issue? Some threads say the starter won’t work if it’s security issue. Thanks for any help

Update
 

[QUOTE=Cuzne;1595979378]hi, new to this site and to owning a Vette. I just bought a 93 40th anniversary edition. The car had a little miss in it that I noticed on the way home after buying it. I changed the plugs and noticed that one plug looked new. After changing it,I tested the cylinder that wasn’t firing , and all was good and she cranked right up . So I changed the remaining 3 plugs , and was ready to go for a ride but now the car only cranks over (rough) no fire. My question is , can this be a security issue? Some threads say the starter won’t work if it’s security issue. Thanks for any help[

I found some bad vacuum lines and replaced a few after resetting the security and got the car to start today after a shot if starting fluid. It started fine a few times after that but after setting an hour it was acting up again. It sounds like the timing is off and coughs out of the breather but finally got it running again and drive it. It’s still missing while accelerating but other than that , it’s smooth as can be. There are no warning lights on so I’m not sure if that means no codes or not. I’ve only had her a week and I’m eager to start driving it. Thinking of changing o2 sensors and already ordered a opti and water pump. Thanks for any advice

Congrats on your Vette and I know the feeling of wanting to take her out for a ride!

I'm confused by your post where you say it misses on acceleration but is smooth as can be?

When you bought the car, was it running on all 8 cylinders?

If you used starter fluid to get her going you may have a fuel pressure issue or a injector(s) going wonky. Do you have access to a fuel pressure gauge?

Did you by chance hose down the engine compartment? or possibly the previous owner..

The basic checks we will ask for,
CEL- any codes
Fuel pressure?
are you getting spark and are you 1000% sure the plugs are in the right order and fully seated. The boot for the optispark are a real pain to get in if your not experienced. They don't line up with each other making it easy to misjudge, I did this when working on my LT1 firebird.

How many miles? Noid lights, fuel pressure test, and spark check.

My money is on the notorious Optispark. Which one did you decide to buy?