I know it's been a while but think we've recently stumbled across a huge electrical issue causing all these codes and stuttering issues. Not really sure but I'll let you guys know more in this forum https://mustangforums.com/forum/showthread.php?t=689728.

 

Ok so here is the deal with what's been up with my car. I did indeed need new oxygen sensors, which I had replaced this past Friday, but the reasoning behind the O2 codes appearing is simply because of the way who ever owned the car before me had the exhaust put onto it. Right now I have a loud clicking on the passenger side when accelerating. According to an exhaust expert, he said that where the two cone like shapes of the exhaust manifold and the exhaust pipe connects against the flanger, there should be some bolts and nuts tightening it down together to keep it from leaking around it, but someone replaced those with something else that isn't tightening it all the way together like bolts and nuts would.

I've also had to have the transmission rebuilt, so now I no longer have the shifting issues. Thank god. lol So as soon as we get it in for replacing whatever is holding the exhaust pipe to the exhaust manifold with actual bolts and nuts, the guy told me it should fix the leak. At that time, I'm also gonna have them run a diagnostics to make sure everything else is doing fine. I'm a little bit concerned with the chime that I keep hearing every now and then while driving. I think it's the driver door ajar alarm, but it doesn't stay on constantly, it actually will chime off and on repeatedly for a bit then go away.