So my Haynes Repair Manual says not to attempt cleaning throttle body because the stock came with some sludge-resistant material and cleaning it might impair performance of the engine. I have the right cleaner, so should I clean it Or not??

 

Based on the number of threads here where dirty throttle body causes issues and cleaning solves the problem, I'd say yes.

 

Clean it. CRC makes a specific cleaner for throttle bodies. They build up a lot of sludge regardless of the coating. CRC also makes a cleaner for the MAF, if your car is equipped with one. If your MAF is dirty a cleaning will work wonders

 

That was the first thing I did when I got mine. 74K and I don't think it had ever been cleaned.
The crud was thick and took some spraying and scrubbing (CRC).
But it completely eliminated the accelerator lag that it had and only cost me a couple of bucks and half an hour.
While you're at it, clean everything.

 

Ok thanks everyone.

 

I have the same thing on my truck TB as well, but I clean it anyways... never caused a problem before.