I have a very mild rpm hunt, or oscillation... barely noticable, but always there after warmup. 4Runner runs fine otherwise.

The preferred method seems to be the use of carb cleaner that doesn't affect sensors. So I have a couple of questions.

1. I picked up a can of Gumout Carb + Choke cleaner. Its say it won't harm O2 sensors, but be careful of plastic and wiring. Is that the ok stuff?

2. Some people are concerned with the flammability. But I've not heard any reports of fire. Common sense use may be all that is necessary, but at my age I seem to worry alot. How "safe" is the carb cleaner on a warm engine?

3. I understand what we are looking for is an increase and steadying effect on the rpm's. Is that because we temporarily seal the leak, or because some gets sucked in (I suppose depending on which vaccum hose) and makes it way to the air intake? Just what is the theory?

Thanks

 

Your theorys sound ok to me. Just dont spray around or at the distributor/wires and you will be fine.

 

I'd say use throttle body cleaner instead. Be sure to use the "small hose" that comes with the can so that you can pinpoint the leak.

 

how bout a propane torch? The carb cleaner Ive used shoots out at about a
million psi.

 

I've never had luck with propane.. It's too hard to get in the cracks. with carb cleaner, my point and shoot is much more accurate.