I've been working my way thru my checklist of DIY maintenance items, and next up is going to be flushing out the power steering system on my '99 Highlander. I just finished watching Tim and Sean's excellent video on doing a semi-complete teardown, including cleaning the mesh filter in the PS reservoir.

Here's the YouTube video: https://www.youtube.com/watch?v=5k61KXRK8bM

Since I'd be doing this alone (no helper), an issue I see is that of keeping the reservoir filled with new fluid -- while the 4Runner is pumping the old fluid into a container. The problem, for me, is keeping up with how fast the fluid needs to be added, and then when done, turning off the engine. If I were to quit pouring new fluid, then have to step away and make my way to the ignition key, I know there would be five or seven seconds where the pump would empty the reservoir and the pump would not have any lubrication. As Tim says, this is not good.

Tim discusses this at the 16:00 minute mark.

My question: is there a way to shut off an engine from inside the engine compartment? A kill switch to connect somewhere that I could just flip while standing in the same position as Tim in the video?

I searched Google for 'kill switch', but all those results deal with theft issues and keeping a vehicle from starting the first place. I'm looking for a switch that will shut off a running engine.

Easiest way I can think of is to unplug your MAF sensor when it's running. Should stop measuring airflow and cut fuel to the engine, causing it to stall.

I take no responsibility for any complications that may arise! It will most definitely throw a check engine light if you do it. It also might be really hard to get it to start again.

I'm pretty sure it will idle just fine (not perfectly) with the MAF disconnected.

EFI fuse
EFI relay
Fuel Pump Relay

Good Luck to ya!

It most definitely dies and will not run. Ask me how I know lol!

Get a friend to sit in that thing ready to shut it off!

I've read that if you have the key in, battery on, but engine off, you can do the flush just fine.

Just jack the front up with tires off the ground so you can easily turn the wheel from side to side, and it'll force old fluid out as you're turning the steering wheel, but not in between turns, so a whole lot slower than with the engine running.

Somebody on our YouTube channel claimed the same thing. However, when I tried to use this technique to remove air out of the system after replacing the steering rack, it didn't work so well. We had to run the engine and turn the wheels back and forth to get the air out. But, maybe it does work to move the fluid sufficiently to renew the fluid. It just didn't make much sense to me that turning the steering rack back and forth without the pump running would sufficiently move the fluid through the system.

Here's the item I just ordered from Amazon:

UPEOR Auto Battery Disconnect Knife Blade Switch Side Post Side Terminal Car Battery Cut Off Shut Off

Won't leave it on the 4Runner permanently, only when needed.

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Can't say for certain it will cause harm on a 4runner, but generally speaking, disconnecting the battery while the car is running is poor form on modern cars.
@SaulG 's suggestions are cheaper and safer.

I've never tried it on a 4Runner, but some other cars I've had will just go into limp mode and keep on running. I'll certainly defer to you on this though.

And I'll second the battery disconnect not being a great idea. The alternator is working with the engine running, if you disconnect the battery it can certainly keep the car powered up. But the battery acts to greatly stabilize the voltage in the system, if it's disconnected the alternator could produce some fairly wide voltage swings. Which could damage electronics.

I bRAD - Thanks for posting your comment, and keeping me from doing something... stupid.

Never Disconnect the Battery with the Engine Running

You've got to have somebody that can turn the vehicle on and off a few times for you. It's pretty simple request for anyone. Hell, grab the post man as he walking by. Better yet, ask the hot MILF across the street for help. Same with bleeding brakes. Why buy a power bleeder when all you need is a helper for 10 minutes. I've had my girlfriend help me many times with different stuff, even filming when Sean isn't available.

@StreetCreeper aka Woody lives in Modesto. Maybe he can help you out.

I used the no engine start technique described in post #3 here:

DIY: Power Steering Flush

It works just as described. I can't explain it, but it does. Great if you are solo.

And as far as brake flushes go, I built a pressure bleeder for less than $10, also using some parts on hand.

Here is the DIY on that:

https://www.yotatech.com/forums/f2/3...e-flush-77409/

See my post #21 from 2010. Used it many times since.

With slight changes, and the addition of an empty paint can and some charcoal briquettes, it turns into a smoke machine for air leaks.

Not saying you're wrong @mtbtim , just a different strokes, different folks thing. Also my GF works her tail off with a 20-mile commute and I usually do my car stuff during the week. I won't wait for the weekend unless I have to. The MILF across the street is a *****.

I’m still out road-tripping for the next week, but if you need an extra hand still when I return — I’d be happy. 😎