I bought a 2003 s type v8 from a old lady one owner. Just perfect inside and out engine sounds like new trans perfect . Ok so I seen the check engine light on when I bought it she said she didnt drive it much in a while . When the car is sitting there it sits at normal temp for 20 mins driving you get a few miles and it starts to get hot. With the miss fires and the getting hot is the cats cloged . Just want to get some support on that before I take a saw to the exhaust. Here are my codes P0171 p0174 p0300 p0301 p0302 p0303 p0304 p0305 p0306 p1316 p1000

 

The DTCs you listed indicate a lean condition causing misfires in several cylinders. DO NOT drive the vehicle under any conditions that cause the MIL to flash as catalyst damage is occurring.

Find and correct the cause of the misfires. Use the procedure in the Workshop Manual to check the fuel pressure, which should be between 3 and 5 bar. If you don't have the Workshop Manual, you can download it here:

http://jagrepair.com/images/AutoRepa...M-Workshop.pdf

 

ya I have everything it came with originally. There is no water going into the engine so it's a water pump the missing idk yet hopefully something not complicated

 

Be certain the battery is perfect because a tired one can cause all those codes.

As you have codes for both banks it's not very likely both cats are clogged unless the car has been abused (i.e. unfixed) for a while and driven quite a bit.

With a good (preferably new and fully charged - do it yourself, don't rely on it being so when bought) battery, which codes come back after 2 warm ups?