Mister Willie

My 84 has this irritating problem of not turning off when I want it to do so. I can turn the key and the engine cranks once, maybe twice and fires right up. When I turn the key off, it doesn't shut off the engine. The electrical stuff like the gas and temp gauge will quit indicating when the key is turned off, but the engine just keeps running. I have to stall it or pull the coil plug to turn off the truck.

The previous owner of the truck told me it was the ignition contacts. The fix was to purchase a new starter. I did this, and put the new starter in today (god what a pain, and I've heard the 3.0 is worse!). Well I wasted my money and time apparently, because that didn't fix anything. I also replaced the wiring harness inside of the steering column. Its the thick pack of wires with a harness on one end and a circular piece that connects to the ignition key's mechanism. This didn't solve my problem either.

so, if my rant/problem makes sense.. Does anyone have any experience with electrical problems like this? Any suggestions?

myyota

It sounds like the fuel cut solinoid has gone bad and stuck open, there is also a small o-ring on the end of the fuel cut solinoid, if its bad or missing it will also cause the problem your having. when you turn the ignition off the fuel cut solinoid turnes off stoping the flow of fuel from the carb. I had this same problem happen to me on another toyota that i owned a long time ago.

Mister Willie

Anyone know where this solenoid is exactly? Is there a way to test it's operating status?

myyota

Looking at the carb from the passenger side you will see a round thing with two wires comming out of it, thats it. it screws into the carb. you can test it buy touching the two wires to a 12 volt source, if you hear a clicking sound its good, if you hear nothing then its bad. also make sure the little o-ring is on the end of the solinoid.

SoCalWheeler71

Whoa there! Before you spend anymore money, check the alternator wiring, if the small wires are switched, it will keep running with the ignition shut off as you describe. Fuel pressure alone will not keep it running, it needs spark.

Mister Willie

I kind of figured that, since we're using distributors, not magnetos, but.. I just want the problem fixed. I'll check the alternator tomorrow too.

Mister Willie

I checked the alternator. Theres 3 wires plus a ground that run into the alternator. I looked at the plug and wires and they don't look like they've been messed with in any way before. If anyone has any ideas, please let me know.

The truck is missing a radio and speakers, as well as dome light and wiring and the clock is unplugged. Could an errant wire be causing some kind of short?

SoCalWheeler71

Unplug the alternator, then start it up, then turn off the ignition (assuming batt holds a charge) if it shuts off like it's supposed to, it's either the wrong alt or the wires are crossed.

scoyota67

You're on the right track with ignition wiring. The problem has to do with your ignition system and providing spark. When you turn your key off... it should be cutting off juice to your coil or some other piece of your ignition to stop the spark.

How worn out is the switch (part you put your key in)? Thats where i would start.

locked stock 84

Surprisingly, autozone has alot of diag and repair info! Try this: http://www.autozone.com/servlet/UiBroker

locked stock 84

I cant get that one to work, I'll try again, http://www.autozone.com/servlet/UiBroker
If not, go to autozone.com and enter your veh info, go to diy then to "sounds like" (yeah, kinda meant for green horns) then to engine keeps running, then follow the yellow brick road......

jbclem

When I saw this thread I thought it sure sounded like an ignition switch problem. I looked at the 1984 truck electrical wiring diagram and the ignition switch has two contacts inside...one contact controls one circuit, power to the + terminal of the ignition coil and to the ignitor. The other contact controls three circuits: one is to the starter and also the backup lights, one to engine fuse and then the voltage regulator, windshield wiper, the combination meter(including oil pressure , water temp, fuel level gauge, etc..), and the third to the cigarette lighter, radio, power antenna, clock, etc...

So it's possible that the first ignition switch contact is broken or sticking in the ON position and the other contact is working normally. It's easy to prove this...just get a volt meter or a test light and test the wires coming out of the ignition switch. Three wires should show power off and on depending on the key position. The fourth wire will show power always on even with the key in the off position.

A test light(with a wire piercing needle point) would be best if there are no bare terminals at the back of the ignition switch. If you've never done this before, now's the time to learn. It's a valuable lesson to know how to read an electrical wiring diagram and use a test light.

About the starter...it usually only works for a few seconds, and when you back off on the key it disengages from the flywheel. It's pretty rare that a starter will get stuck in the always ON position; there's two ways I've seen it happen: one is with the starter gear engaged with the flywheel teeth ...actually the starter gear(teeth) doesn't retract and you'll hear lots of awful grinding noises because the starter gear rotation doesn't match the engine rpm once the engine starts. The other way is when you turn off the key (ignition switch) and the disengaged starter motor keeps running and eventually runs down the battery. You can usually hear this but if the starter has a quiet motor and it's noisy outside you might walk away from the car and not hear it.

Hope this helps...

jc

Mister Willie

Ok. I unplugged the alternator, and it shuts off like it's sposed to!! YES!

So. If the wires are in fact crossed, how do I tell what wires go where? One thing I did notice is that the ground wire from the alternator did not just ground into the frame somewhere. It goes in and gets all wrapped up with the other alternator wires and they all lead into a box on the left side of the engine compartment that reads 'IC (something(I just had it in my head not two seconds ago))' I'm assuming thats Ignition Control right? Should the alternator ground right into the frame instead or is there some special purpose there in IC?

XtraSlow_XtraCab

The "IC" thing is the voltage regulator. What IC means, the hell if i know. But I can't imagine the ground running with all of those hot wires and into the regulator. My money is on two "post wires" being mismatched. I would think it lead off to ground somewhere. I'd check mine, but its midnight right now.

Mister Willie

OK, I wish I'd have read a little more closely earlier.

If it helps.. The backup lights are NOT working! If that circuit is shorted somewhere, could that be causing this problem? Also, the radio is pulled out, but the clock doesn't work. I was told it just needs to be plugged in(previous owner) and I haven't checked that yet as I wasn't concerned with it.


Does anyone have an 84 wiring diagram? I have my haynes manual but it just gives early model or typical late model diagrams and none of them match my truck completely.

Mister Willie

I started the truck and off I went to work. I get there and I'm rolling up under the assumption the key is not going to turn the truck off. I turned the key off while rolling and the engine quit!! YES! but NO! Anyways I rolled to a stop and a lady was just getting out of her car next to me and I look at her and said.. Quiet truck huh?

So now the key works. All I did was start investigating wire colors and where they go from the alternator, igniter, ignition coil, and ground connects. I removed some of the Electrical tape on the wiring to see what was going on... It had to have been a loose wire somewhere. Its great that the truck turns off but.. Man.. That means the problem has the potential to come back, cause I didn't locate the problem.

Anyways, long story short, I took the truck out after work and got out on some dirt roads. Got going about 50mph in some spots. That road is pure excitement at that speed... sliding around, dodging ruts and bumps, watching everything go by so fast.. then BAM.. a mud puddle. I slowed down to about 40 and water just went everywhere. Even inside.. it was great!!