Running 5000 RPMs in neutral when using A/C at high speeds
 

The Honda dealer and my mechanic have two different opinions, and I need
more advice before I go with either repair.

Car: 1999 Civic LX, manual, 150K miles

Two main symptoms:

1.) Sluggish when I first depress the gas pedal. In every gear
intermittently, but alsways when I'm in second gear, there is a hestition,
then it kicks in.
Giving it more gas doesn't help.

2.) When driving high speeds for an hour or more, running the A/C, tt revs
as high as 5000 rpms in NEUTRAL. This was fixed when my mechanic cleaned
up the throttle body, but it just happened again yesterday. After the car
sat for an hour, it started up no problem. No revving in neutral.


The dealer said its the catalytic converter (based on a code reading), but
my mechanic said the converter is clean, looks good.
My mechanic is suggesting that its something in the throttle body.

Any advice, thoughts, similar experiences?

Thank you!

Sarah