1991 Isuzu Stylus - Throttle Body Problem

[1999montana]

Thought I would post this in the right forum.

We have a '91 Isuzu Stylus with the SOHC 4-cylinder engine (automatic). It has been well maintained and received new 'everything' about three years ago after a minor fender bender (injectors, shocks, lower ball joints, front hub bearings, rotors, calipers, wheel cylinders, flex hoses, exhaust, muffler, tires etc) It has about 148,000 Kms on it (mostly short trips) but recently has developed a sticky gas pedal problem.

I think the inside of the throttle plate and possibly the inside of the throttle body has varnish or deposits that cause the throttle to stick after the vehicle sits for a while (usually about a 1/2 hour). After the first poke, the throttle frees up, until the vehicle is parked again.

I notice that it runs a bit rough at idle, but off idle it runs smoothly. I think I know the cause. Gum or varnish, but I'm unsure of the cure. I have some Gunk Carburetor cleaner normally used to clean the throttle plates and choke on a conventional carb'ed vehicle.

Does anyone have an opinion as to whether this carb cleaner would harm the intake or any part of it should I decide to spray the stuff inside to clean up the throttle body and plate?

Any thoughts would be appreciated.