Got a wierd one here..

Switching my wipers to high stalls the engine. rpm are good on the way down but once it heads back up they drop. this happens 2-3 times until the engine stalls completely. Anyone ever had this happen?

So its like this:
turn wiper on to high
one pass up: rpms drop
one pass down: rpms stabilize
up again: rpms drop
down again: rpms stabilize
up again: car stalls

edit: ok so now its doing it at any speed, but this helped me isolate when it happens, the audible click the switch does when it either goes up or down is when the rpms are affected.

Time to overhaul or replace your wipers. Common factor with electric motors is
when resistance increases they draw more current to overcome it. So the amperage
draw increases, thus leaving little power for other things. A good little test is turn
the wipers on high speed, while they are on turn your headlights on full high beam.
I bet the head lights will go very dim or no light or the wipers will stop.

Once I had a 4x4 and I installed a large electric cooling fan. When the engine was sitting
at idle and the cooling fan came on, the idle speed would drop very low and sometimes the
engine would stall. It turned out on starting the electric fan would draw in excessive of 50
amps. Not much power for anything else. Oh I eventually noticed the insulation to the fan
wires had started to melt. (15A wires) Haha lol. Yeah I ditched that fan.

When the wipers ore on full, check out whether the wiper motor is getting hot. Note it might
not be the motor at fault, but the wiper mechanics binding. (need cleaning and lubricating)

Just a thought.

Yes, try cleaning it.

Also, once ones the bench, try an bench test with amp meter. Three is a mechanical switch outside that switches power/ground. There might be enough goop/other to cause a short.

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Ok so...after alot of diagnosing i came to the conclusion that the problem was in the driver side fuse box. So i rewired and resoldered ever...single...connector. it was on its way out anyway and luckily ebough last year a 165 popped up in the scrap yard near me and it had a mint fuse box so i scooped it up. My old one was rotting from the inside so it needed it anyway but, that didnt fix it. So with the entire dash removed i did some digging. The car is being told to shut itself off, with the wiper motor disconneted its still doing it. When i trun the wipers on it seems ok but when i switch it off the car tries to shut itself of. This doesnt seem to be an amperage probleme more like a short. Any ideas are welcome

K so i hooked em up to the battery directly so its not an amp problem for sure.

Im on the verge of just wiring it up with a relay and switch. Itll just have one speed but at least itll work. But on the other hand id love for it to work properly as toyota wanted it to.

You'll have to diagnose the steering column wiring harness routing to the wipers motors looking for a short. It'll be a lengthy process as you'll need to check every wire against every other wire.

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Been through that already, spent about 8 hours probing the crap outta all that but now things have gotten worse, applying the brakes does it, turning on the heater does it, and now code 12 popped up. Im thinking my alternator is on its way out, not putting out enough amps to handle all the extra load. Thing is the charge light hasnt lit up and voltage at the battery is good, ive heard this can happen but is pretty rare

How are the grounds? Maybe take some jumper cables to add a couple extras, run one from the alt to the hattery positive and see what happens.

The charge light is working on first start right?

Voltage dropped every single ground on the car, as in ALL of them and all were well within spec(not one was over .02). Reset de ecu this morning before starting it for good measure also. And at this time the car is, for some reason, fine. Stupid electrical gremlins. I hate when a car magically fixes itself, it leaves to much room for doubt and for the problem to arise again at the worst moment.

As far as i can tell for now is water/humidity made its way into the engine fuse box. it looked pretty damp when i popped the underneath cover. Maybe some strange shorting was happening, it was raining here for the past couple of days and seeing that the car is slammed with rolled fenders the fender liners needed to be removed. its back to freezing temps outside now and it runs perfect. im not satisfied obviously but i am going to look into better water protection for the underhood fuse box.

There should be engine under covers as well that run from the bumper to in front of the drive shaft.

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yeah there SHOULD but there isnt lol. i bought her in 2003(my first car ever when i turned 18) and the amount of stuff that was wrong /missing from the car was insane. its safe to say i pretty much saved her from the scrap heap a few times now. aside from the interior and front/rear bumpers not much is left from the original car, i even redid the floors front to back last summer. theres probly about 7 st16x cars in this one, and i guess 1 st205 with the swap lol

so i gottta bring this thread back, as expected it started doing it again only now it worse. started missing like crazy while driving and sounding like popcorn at higher rpms.
Pulled out the 205 bgb and decided to start testing ignition components

So before i start pulling everything out i want to do thing one by one and get your input

Pulled the igntion coil out and performed the ''cold'' test, bgb says i should have i should have 0.36 to 0.55 ohms in the primary and 9.0 to 15.4 kohms in the secondary

Primary gave me 1.2ohm ( out of spec)
Secondary gave me 12.3kohm ( within spec)

car still starts and drives ''well'' until it starts missing at random times and wiper problem seems to come and go as it pleases. So what do you guys think? Need a new coil? im thinking yeah. does it have anything to do with the wipers stalling the engine? im thinking no.


edit: also went ahead and tested the dizzy and plug wires per the bgb and all were well within spec.

im wondering that if resistance is way to high in the coils primary maybe turning on the wiper motor sucks too much juice out of the car wich could cause the ignition to cut out. im not betting on that though.

Alternator good ? A dying voltage regulator can cause these exact symptoms.

im about 100% certain that the alternator is good. battery voltage is perfect and doesnt drop when turning on the wipers. also, i disconnected the wiper motors connector and ran them right of the battery and the car didnt want to stall like it does when the connector is on and i switch the wipers on.

But i think might have made a small discovery here

i pulled out both main relays a few days ago to test them but before i explain a bit of history on my swap

3rd gen engine from a 205 front clip
running off of a sw20 ecu
wiring was done by tweak about 9 years ago

Now the ignition main relay in the sw20(part number 85925-17010) seems to be specific to the mr2
This relay is nowhere to be found on th 202/205, im sure its there but its a different part number.
Now in the bgb for the 202 this relay(5 pin) should not have continuity between pins 2 and 4 when voltage is applied to it
But for the sw20, and unless its a typo in the bgb, the sw20 ignition main relay SHOULD have continuity between pins 2 and 4 and 4 and 5 when voltage is applied to it.

Now when i pull the relay out and test it im NOT getting continuity between 2 and 4 but AM getting continuity between 4 and 5. So unless its a typo in the bgb this relay is not operating per specifications.

Now obviously it would be awesome if my problem is a simple dead relay and im going to go to the scrap yard later to pick one out and test it, we got this relay in many other toyotas here so im sure ill have my pick at them.

But anyways, what do you guys think? bad relay or typo in the bgb?

edit: yeah its a typo, just got back from the yard and had about six of em in my hand, they all tested the same as the one off my car.

Yeah, your ignition relay isn't going to cause all those problems.

Your problem is going to be somewhere that effects the whole car. Like your grounds all badly corroded. Or fuse box corroded. Maybe one of the main power wires is corroded/damaged. Or that junction box in the drivers kick panel (can't remember what it's called).

How old is your battery?

As stated in my previous posts. All grounds tested perfect, interior drivers side fuse box has been complety replaced and rewired(took 3 days to get done. Though i do agree with you that the problem is elctric. If it wasnt winter and -35 outside id probly strip the entire cars harness. Sounds extreme but im at that point now.