Whenever I turn my truck on and if I let it idle for too long it starts to sputter and make a really loud high pitched hissing noise coming from the engine. I have a gutted Catalytic Converter and I know my O2 sensors are bad but It sounds like an air intake problem to me but im not sure. I'll try to get a better video of it later so you can actually see and hear what it's doing. It happens without fail nearly every time I start the truck and let it idle for a few minutes. I noticed also that the engine starts to shake and wobble violently as if its miss firing possibly? I don't know what the deal is. My RPM's are speratic as well, they drop to 250-300 RPM at times and I give it gas and it takes it a few seconds to actually start climb in the RPM's, like its almost flooded..Any help would be great! Also, some input on a decent Catalytic Converter that is California legal but hopefully wont rob me of performance would be appreciated as well as O2 sensors. Im full of questions today 
heres a link to a youtube video I just posted up so you can hear what its doing.
http://www.youtube.com/watch?v=1RaQ-aZvn0Q
heres a link to a youtube video I just posted up so you can hear what its doing.http://www.youtube.com/watch?v=1RaQ-aZvn0Q
