98 gt rough idle and loss of power Please Help!!
For about 6 months now I've had poor throttle response and bad gas mileage on my 98 GT. When I start it up cold, it runs like a champ but when it warms up, it has poor throttle response. About a month ago, it started to have a very slight miss at idle and has progressively gotten worse. It also sometimes has a weird kind of slow start. This all seemed to start happening when I washed the engine with water and changed the battery. So far I have changed the fuel filter, cleaned the maf sensor, replaced plugs and wires, and I am now wondering if it might be my fuel pump or regulator. I don't know much about mustangs so any help would be greatly appreciated!