[zach1989]

I have an 03 focus Ztec 2.0 dual cam. I have had issues ever since I bought it. When I bought it the radio was toast and the radiator fan resister as well.

I'm losing alot of power I can't use the ac or heat at high power cuz the transmission won't shift right. Also will dim the headlights. I'm pretty sure guy before me might have shorted out the system.
I have a new battery and altinator.

Also when the ac is on feels like I lose alot of horsepower car has a hard time getting up to speed.
I have put alot of money into this car and don't want to scrap it.

I'm going to take it to a shop. But don't want to spend 1000s trying to figure it out.

Wondered if anyone has any ideas on what to look for or what the issue could be? My mechinac said it was electrical but would like to know possibilities so I don't get overcharged looking at stuff that might not matter.

Any input would be greatly appreciated. Thanks zach

 

[sailor]

Gotta start with basics IMHO

Removing & cleaning all the major contact points for the main wiring along with checking it's condition to start.

Battery terminals, grounds by the battery & to engine, hot connections to starter/alternator/wiring harness.

When you're worried about putting $ into a car, I always recommend a compression test on the engine to give an idea of it's overall mechanical condition.

Welcome to FF!