IAC valve could be stuck open. Take it off and clean it with Carb Cleaner. Also clean the seat on the TB. Check your throttle cables and TB operation.
Here’s how to properly set your idle:
1. get engine to operating tempurature. turn off ac, radio, etc.
2. disconnect IAC (idle air...
Never heard of them. If money is tight spend about $10 more for some Kumho's which are Z rated. They will last longer and will probably hook up better. My philosophy is don't skimp on tires.
I've heard more bad things about the Dallas Mustang Mils than anything. Buy the splice-in kind from http://www.ponyexpressperformance.com/mileliminators.html
I've bought mine from here for both my Mustangs and have never had a problem. (Knocks wood)
Just make sure you wrap them real good...
I see you have an aftermarket midpipe. Just a warning, if it ends up being a blown out cat on that x-pipe, they won't do anything except charge you $80 for their time. Warranty doesn't cover that. My advise is to narrow the noise down yourself before you take it in. Put the stock H-pipe back...
I agree with this. Even if it is a used low mile '03 who cares. It has a full warranty. Even the used Mach 1's are going for $24-25K. There are alot of brand new '03's at the dealerships. They have to get rid of them ASAP. Use that as a selling point and talk the price down.