5.7l tbi missing firing

[Mr.hillbilly]

So for a couple months now I’ve had a slight little misfire at idle and I thought it was my spark plugs and so I changed them out and now my trucks misfire is worse than it was and now and its bogging when driving it any clue of what’s going on? And I made sure that all the spark plug wires were tight. The spark plug plugs are gapped correctly. I double check the firing order and from what I can see my fuel injectors aren’t dripping fuel and have a good spray pattern.

 

[Mr.hillbilly]

I meant to put miss fire

 

[ktmoutfront]

If the new spark plugs are correct and gapped correctly, the only other thing you touch were the plug wires. They may be failing. Start the truck in the dark and look for arching.
Put a timing light on each plug wire and watch the light for consistent flashing. I have found issues doing these simple tests.

 

[Blue85]

It's not hard to crack the porcelain on a plug, which can cause a host of issues. It's also easy to melt a wire on the exhaust manifolds. Re-trace your steps - mistakes happen. Bad parts out of the box happen a lot these days, too.

 

[Wes Harden]

Does the miss fire get better or worse under load ?
Do you have vacuum gauge?