Well, I would check compression on all cylinders, you could have a mechanical missfire like from a valve problem.
If compression is low on that cylinder, you will need to remove the valve cover first and make sure valve springs and push rods etc. are all ok. If ok, then the next step is to remove the cylinder head and send it to a machine shop for a valve job.
Double check for a vacuum leak under the hood first, I have been fooled before!!!
How to check for a vacuum leak
I cleaned the throttle body, all around the engine and cylinders and I just checked for vacuum leak and a PCV hose had a long crack in it, I will replace the hose, could this be the problem? If not , I will check compression,
I really appreciate your help.
Hello again Reggie,
The pcv hose COULD be the issue causing a vacuum leak like I suspected, would be worth repairing first before you spend more time and money. You might want to check for vacuum leaks around the intake manifold as well, with a can of WD40 or propane tank with a rubber hose attached to help you locate the leak. Keep all flammables away from spark plug wires or anything that produces a spark 🙂