Cylinder misfire

I replaced the fuel injector fixed my problem paid $78.00 for the injector.

I just had a check engine light for a #3 Cylinder misfire. Along with the light, the engine started running rough and I can hear a tapping. The check engine light was reset and I replaced the #3 spark plug and the ignition coil. The light is still out, but nothing else has changed so I know the problem is not fixed. Any info would be greatly appreciated.

My guess is the hydraulic valve tappet is starting to stick.

My truck is currently running on 7 cylinders due to #4 cylinder bad what should I look for in repair cost including timing change

Its the valve

Thank you, I really appreciate it

My truck its been shaking since I bought it. At the beginning I did a tune up, plugs, wires, cap and rotor. But still the same I check for codes and found 3 misfires on 2, 7 and 8. I erased them, ran it and checked again an gave me 4 misfires in cylinders 1, 3, 5, and 8. I did a compression test but everything is normal. I don't think is the injectors because of the different misfires. I'm starting to think is a sensor problem even though I don't get a check engine light. Can you help me?

Ram 1500 Van

I have a misfire in cylinders 3 & 4! I changed rotor, cap, wires, and spark plugs and it's till misfiring. My scanner is saying P0300, P0303, P0304. Before I start throwing parts at it I thought I might ask.

Wouldn't that make the other cylinders misfire also? I have a constant misfire on the 3 and 4. The 3 and 4 are the center cylinders on the right and left bank that are misfiring. I thought it might be bad injectors but before I got them I did a compression test to make sure and this what I found.
1. 120psi
2. 120psi
3. 90psi
4. 90psi
5. 120psi
6. 140psi

I'm guessing "intake cracked"?

Ok here is an update on the Van.

I got to thinking about the low compression in 3 & 4 and I'm NOT a pro by any means but I couldn't see how a cracked intake would result in low compression like I 1st thought. I can see a misfire but not low compression. So I got to thinking ether bad valves or rings. The motor has 130,000 on it so my guess was the valves. With noway to do a leak down test I shot a squirt of oil in the 3 & 4 to see if compression came up but very little changed. Next I hook my air compressor to the 3 & 4 with them at TDC put about 30-50psi in and I had hissing and air coming out of the exhaust pipe.

So I'm thinking bad exhaust valves

Ive got a 2002 dodge ram 1500 slt w/4.7L engine. I am getting a misfire on the #6 & #8 cylinder. I have changed the plugs with bosch platinum 4 (all 8) and have also changed all 8 coil packs and am still getting a misfire. I pulled out those 2 plugs again and there is a carbon buildup on both. I also checked the others and they seem to be clean. Any ideas on what else to look for

I am having the same issue as well and nothing seems to work to fix the problem. New Plugs, coils, air filter, clean the throttle body and still the engine revs 400-800 RPMs while in Park and when driving over 50MPH. This is driving me nuts. Anyone have suggestions?