i had a similar problem on my 2001 3.8l mustang, when we hooked it up to the computer it said that one of the pistons was misfiring. i replaced the coil but it didnt help. turns out it was the catalyctic converter. it was plugged up and the exhaust fumes were not able to escape properly. hope this helps.
Feb 04, 2010 Rating
nEED hElP and AdVicE by: Jose A
im having the same problem and still have no idea what to do. did u figure it out yet. i have exhausted all options to figure it out and have yet to get it repaired. thanks
