I would like to install some type of high idle controller on my 93 subaru wagon. I know this is something you usually see on emergency apparatus, and not on a station wagon, however with the current load at idle on my car is sometimes quite excessive.

 

I know that most people would just reccommend dropping in a larger alternator, or installing an underdrive pully, however I am not a big fan of either. So you would need to do some convincing, especially since the normal day-to-day current draw is handled easily with the current alternator.

 

Any Ideas?

The first thing I would try because it's cheap, simple and would probably work is to replace the alternator drive pulley with a marginaly smaller one. I dont think it would take a big difference in diameter to produce the effect you're seeking.

I would go to an alt rebuilder place and try to find one that would fit on the alt drive shaft.

Anything else would have you mess with things that are complicated or could «backfire».

Just my opinion.

Good luck!

I would install an idle solenoid from an old air conditioned carbureted car. My '71 cadillac had a whopper of a solenoid on the carb. It may take a little fabricating to get the plunger to press on the throttle. Interlock the switch with park or neutral. Voila, high idle controller. Very simple, easy to remove, and reliable. It also won't interfere in any way with the IAC or computer.

PM Legacy777 , or do a search on the subject - I think he successfully boosted his alt output.

yeah I have a HO alternator. Cheap solution for high idle controller. Stick a feeler gauge or penny for that matter in between the idle stop and throttle. Instant high idle.

Unfortunately that is a bit difficult to do instantly when I am stopped on the side of a snowy road at an accident

let me think about this and refer it to one of the electrical gurus on the legacycentral bbs.

Josh - I'm an electrical guru? Cool.

 

EOppegaard - There are two sensible approaches I can think of (both are untested since I just came up with them):

 

1) Use the cruise control actuator. If you want to take this approach give me a few days and I'll try to figure out how that would work. I personally think this would be a really cool way to do it.

 

2) Install another solenoid in parallel with the stock IAC valve. You could tap the brake booster hose (before the check valve built into the hose) and drill a hole in the plastic intake pipe and install a barbed fitting on it. Or maybe just tee off the IAC hose or a PCV hose instead of the latter. Then connect them with a solenoid controlled by a switch in the passenger compartment.

 

If you want a spare plastic intake pipe and to experiment with and some solenoids that look like they might be appropriate, I think I can help you out. PM me if you're interested.

 

If you go this route, you should probably also trick the ECU into thinking the throttle is open (you just need to ground the idle switch wire), since otherwise it will try to adjust IAC valve duty cycle to bring idle back down to spec. Even if the idle speed when it does this is acceptable, it will screw up the learned idle control parameters when you switch the high idle off.