Check Engine Light
 

I received a check engine light on my porsche not to long ago. The guy I bought it from says that it does this because of the O2 sensor is ahead of cat. coverter for bank 1. He told me to use this Durametric software to reset the codes. I did this, but I noticed that there was another error code for the check engine light.
P0507: Idle Air Control System

Upon receiving this error, I actually started noticing that upon startup, it would idle all over (700-1500). I was reading up on other forums and somebody with that problem said that they cleaned the throttle valve/body, put some fuel injector cleaner on, changed fuel filter, and checked for intake leaks. After this, the CEL went away for good. I'm not very car savvy and don't even know how to clean the throttle valve/body(or even what it looks like)on my car which I just bought used. Since this is a mid-engine vehicle, I don't even know how to get to the engine. This is a new experience for me and I was hoping someone might be able to post some pictures with some subtitles explaining the correct procedure for this if I wanted to follow what the guy did who previously had this exact error. Thanks in advance.

RE: Check Engine Light
 

I'm confused as to why you would reset the CEL light without replacing the O2 sensor? It is bad, replace it.

As far as the IACS, could very well be due to a vacuum leak somewhere in the system. To access the top of the engine, you need to raise your top slightly, then remove the carpet and engine cover from underneath the rear of the top. Then you can disconnect the intake tube and remove the throttle body to clean it.

RE: Check Engine Light
 

The guy told me that the O2 sensor not being replaced won't really hurt the car, but will instead have an adverse effect on the efficiency of the car. Basically, I was informed the the price it costs isn't worth the price it saves. Maybe I've been misinformed? A picture would be really helpful if you are able to provide one for the throttle body/valve. Any special chemicals I should use?

RE: Check Engine Light
 

Yesterday I removed the throttle valve and cleaned it out. I had to disconnect the throttle sensor to do this. When I put it back, the CEL was removed. Unfortunately, later that night it came back on. If I want to check for leaks, what is the best way of doing this?