Sorry guys, I should have explained better. I hollowed out the cats and while I had the pipes off I replaced the 02 sensors. I figured it was worth replacing since I had the pipes off. Any help or ideas would be awesome. I'm just sure what to check next...

 

And no I put the mid pipe back on before trying to start it.

 

Any other codes?

 

Okay, here is the latest. I started thinking about what to check. I decided to check the vacuum on the car. FOUND THE PROBLEM!!! I believe the intake is leaking and I have no vacuum. My question now is; what intake should I put on this car? All stock motor, I just don't want to put that junky plastic intake back on the car. Does anyone have any suggestions?

 

You mean the "junky" one that lasted 12 years?

Just get a new FRPP manifold and you'll be good for another 8 to 10 years easy...

 

Yes, like the "junky" one that lasted 12 years. Plastic intakes are not a good idea and with a pending class action suit against GM for same problem and the notorious nature of plastic intakes on Ford Mustangs. Here is a little article I found for your reading;

The situation is made worse because the engines are V-type units, so the manifold has to for a bridge between the two heads. Although the heads are machined with precision, the angles of the various faces are not always exactly the angle they should be, so when the manifold is bolted down, there is a danger that the manifold is being distorted to fit the faces – this cannot happen with an aluminum manifold.

This why there are so many mustang manifold problems and GM intake manifold problem. They are all to do with plastic manifolds. Ford, GM and other auto companies went to plastic for intake manifolds to reduce cost and weight, and some cases they did not allow for the problems in the situation. The plastics used can withstand the temperature of the cylinder heads on an in-line engine, but with a V-8 there is a lot of heat coming up to the manifold, which makes it worse. Of course, the under-hood temperatures of modern engines are very high owing to the catalysts. This also makes intake manifold problems more likely.

 

My point is that it lasted 12 years. Mine started leaking when it was 9 years old, I did not hesitate to buy the FRPP replacement which presumably will get me through to at least 2020.

Also, "The situation is made worse because the engines are V-type units, so the manifold has to for a bridge between the two heads. Although the heads are machined with precision, the angles of the various faces are not always exactly the angle they should be, so when the manifold is bolted down, there is a danger that the manifold is being distorted to fit the faces – this cannot happen with an aluminum manifold." is patently untrue.

If the manifold and the intake ports are not in perfect alignment then the weaker of the two (almost always likely to be the manifold be it of plastic or aluminum) will have to deform to for them to mate up properly.