Hello.. I bought a Ford Scorpio 2.0l built in 1990 a week ago and now have problems starting or starting. The car had a battery with 54 Ah installed and ran well for a few days. After that I installed another car radio, subwoofers and power amplifiers and since then have problems starting. Since I have often installed systems in cars and have checked my wiring harnesses several times, I am sure I did not make a mistake. Since the up to now The car can only be started if I cross over with another car, but then without any problems. Alternator runs and produces good power, the car does not run out once it is on. However, somehow the battery is not charged during the ride and therefore The car can’t be started any more. Has anyone ever experienced something like this or does anyone have advice? Thank you very much. Greetings, Tim