1997 mercury cougar xr7 3.8 had a p0340 code this told it does not matter how you set your camshaft so I just put the new one in and it runs like crap can you help please
The camshaft must be properly timed to the crankshaft for the engine to work properly, Check out the Haynes manual for this vehicle for detailed instructions.
I look up on all data it shows me to put the camshaft 54 degrees before that I took out number one spark plug turn the harmonic balancer in telling fill air then line up the timing marks should I try to line up with crank shaft
Sorry, but I don't understand what you're saying.
Should I line the timing marks on the harmonic balancer to the crankshaft?
The harmonic balancer is keyed to the crankshaft and can only go on one way. It's all the other stuff that must be properly lined up. Please spend the $12 bucks and get this workshop manual, follow the instructions and you'll be doing the job correctly. I have experienced your frustration and can relate. This will be the best $12 you ever spent.
https://haynes.com/en-us/mercury/cougar/1989-1997