206 Unsolved problem in my vehicle

Hello friends, I am a 206 1.6 2001 gasoline model user from Samsun. My vehicle has started to have problems such as low traction, black smoke, popping, raw gas and gasoline, and shaking. This occurs both on gasoline and gas. The case was replaced without ignition but it did not fix it. Everything necessary was done with a mechanic but no problem was found with the engine. I found an electrician and explained the situation to him, he said it was from the brain. However, he did not say for sure, he said we will try it and if it fixes, it will fix it, if not, we will look at it completely. The entire exhaust was replaced before these incidents happened to me. I am wondering if this could be caused by a faulty exhaust. Could it cause such problems? Has anyone encountered such problems? I would appreciate any help.

Close the LPG valve. Pull the fuse. Use it the same way. Generally, the coil is changed, and the spark plugs and spark plug wires, if any, are changed in these cases. I bought it thinking it was an original coil at the time, but it acted like a defective coil. I noticed it worked better when I bought a Delphi.