I recently had a tick coming from the drivers side of the engine which I assumed was a lifter tick so I replaced all the drivers side lifters and the tick is still there, only this time it's worse than it was originally. Ever since I replaced the lifters it has started feeling a little sluggish. As I was coming home from work today I got on the gas a little harder than I should have and ever since then my car has been acting odd. The engine has a slight shake to it that you can feel throughout the whole car while driving and idling. It also feels even more sluggish than it did after I replaced the lifters.

Does anybody know what the issue might be? Did I replace my bad lifters with worse lifters? I'm at a loss right now so any suggestions would be appreciated.

Additional info:
2000 3.8L V6
Plugs and wires were changed >1k miles ago
Changed the oil >200miles ago
Lifters were changed >200 miles ago
I rolled the pushrods on a flat surface and they didn't seem bent

 

Right lifters?
Misfire on a cylinder or two?

 

I started pulling the plug wires 1 by 1 to see which cylinder wasn't firing and when I pulled the wire for cylinder 3, nothing happened. I pulled the spark plug and it looked fine, pulled the plug wire off and it looked okay, then I put a spare plug wire on and still got the same result.

Now that I know where the issue is and it seems like it isn't the plugs or wires, what could it be?

 

If its not getting a spark to one or more wires it needs a coil pack.

I suggest Motorcraft although MSD should be ok too. I just trust Motorcraft more with these Mustangs.

 

When I pulled the plug wires from the coil pack they were all getting a spark. Including the wire to cylinder 3.

Could it be a fuel issue? Fuel injector maybe?

 

Oh I thought you said there was nothing there even with a spare wire. I took that as no spark.

If it is getting spark and fuel to the rest Id check the injectors ya.

 

So I'm not sure if i missed it in my initial checks or if it somehow just happened but I don't just have 1 cylinder misfiring, I have 2. But anyway, I got a spark tester to check for spark between the plug wires and plugs and there is a spark between them. I also bought a stethoscope to listen to the fuel injectors and 1 injector to a bad cylinder is not firing at all while the other injector to the other bad cylinder is. When I pulled the plug to the cylinder that has the injector firing, it was covered in black soot and smelled heavily of gas.

Is it safe to assume that I have 1 bad fuel injector on one cylinder and 1 bad plug on the other?

 

Me Id probably just replace both injectors and plugs.

 

So I decided to replace both injectors and spark plugs like you suggested and it's still misfiring but now it only seems like it's cylinder 3. I put a stethoscope to both injectors while the car was running and I could hear them both firing like they should. When I started the engine I could immediately smell gas that I think was coming from cylinder 3. It also sounded like cylinder 3 was trying to fire once every 4-5 seconds.

So this is what I do know.
-Fuel is getting to the cylinder.
-Fuel is not being burned.
-I am getting spark to the spark plug.
-I replaced the spark plug and the problem persists.
-Cylinder 3 is trying to fire.

Could the cylinder just not be getting enough spark? Would that be a coil pack problem?

 

Ive never had a on / off spark or a low spark like that so cant say to that. Maybe someone else here has that or did before. But Im not sure what else it would be but coil. Hate to throw money at it by guessing though.