sudden low power of my car

sorry for the lack of info. I already replaced my air filter and fuel filter a few month ago. 1st i encountered it i had a major tune up done. it worked for a few weeks then it happened again the 2nd time around. this time with a loud clanking noise in the engine. I had the crankshaft gear replace(due to its deformity) and had my head cylinder overhauled(top overhauled as some would call it). thanx for all the help i can get.

Could be car plugs that need to be replaced from time to time or your breaks might be slowing down your car? Could also be problem with fuel pump. But the clanking might be be because one of the straps is not tighten. Don't know how much you know about cars but hope i gave you some ideas.

I hate to be the bearer of bad news, but perhaps you blew a piston or have a broken rod. This would explain the lack of power as perhaps you are running with one less cylinder. This is going to sound terrible, but that loud cranking could be a rod knocking or something, and if that's the case you're looking at a few thousand dollars for repair more or less.