Need help after changing fuel filter

My Caprice was running rough, particularly after adding fuel treated with Stabil, so I changed the fuel filter with a K&N filter. Now I cannot get the engine to do anything but turn over. A little background on the car: I just bought it from a small mechanic shop whose owner told me the engine had been changed with another LT1 around 2 years ago and the car has been sitting for a while. I was able to drive it even though it was running rough until I added the 3 gallons of gas with 1ml of Stabil added. Any ideas?

Can you hear the fuel pump priming?

I left my Camaro sitting 2 years, started it, drove and the fuel pump went next time I tried to take off.

Yes, I was wondering if I needed to click the ignition over to let the fuel pump build pressure. But yes I can hear the fuel pump cut on when I turn the motor over

I'm going to try adding more gas tomorrow along with some Seafoam. There was plenty of fuel in the line when I changed the fuel filter

Have you checked for fuel pressure up front since the change?

Not yet, I have to find a fuel pressure gauge that I can afford to borrow. All of the local parts stores are asking too much of a deposit

Def start by checking fuel pressure at the rail and report back.

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Something obvious just dawned on me. My garage bay that the Caprice is in has one side open and I left the hood open while it was raining pretty hard. So it is possible the Optispark might have got a little wet.

"Little wet" isnt gonna do it. Start with fo and lets work from there.

LTXtech.com IS my drug...
OWNER/ADMIN

Today I'm going to remove the new K&N fuel filter I just put on to make sure I didn't do anything idiotic like put it on backwards