starting problem turns to shutting engine off problem

1995 Tacoma, 2.7, 4x4, factory stock, 114,000 mi. 2 weeks ago I started experiencing starting problem. Clutch depressed and turn key, I would hear 1 click and nothing would happen. After a few tries the engine would start. This was intermittent and the engine would on first try most of the time. I tested the battery (12.8 volts) and tested the starter relay and the wire/ground connections. For the last 5 days the engine started every time w/o fail. Tonight I started the engine and heard a noise I had'nt heard before and thought the solenoid/starter failed to dis-engage. I turned the engine off and immediately the engine started w/o touching the key. I had to disconnect the battery to stop the engine as it would restart as soon as i shut it off. I reconnected the battery after a few minutes and went in the house (key in my pocket). Aminute later I went outside to find the truck trying to start itself and had to disconnect the battery again. (no remote start on truck) Any help would be greatly appreciated.

 

So the truck cranks on kts own?
But doesn't start?
It just sits there and cranks?

Pull the starter relay.
See what pins have power to them with the key OUT of the ignition.
Only pin 5 should have power.

 

Thanks for your response. The truck starts and runs on its own if key is in run position. if the key is in off position or out of the ignition completely, the truck cranks itself but doesnt start. cranks non-stop until it either starts or battery is disconnected. i took the starter relay out before and had continuity on pins 3 and 5 i think it was, but nothing with any other combo. also used pigtail from battery to the pins and relay would click. I will check the relay as you suggested and update what i find out.

 

UPDATE:when the battery was hooked up and not trying to start, I removed the starter relay and #5 pin was the only pin that lit the tester with key turned off. When TRYING TO START ITSELF WITH KEY ON OR OFF #5 AND #3 WERE LIT. I pulled dash cover and tested the ignition switch. white wire and white/red wire were hot with key off. Accessory wires Black/Red, Black/YELLOW and Blue wires were hot when key was in run position and Black wire (START WIRE) only lights tester while key is turned to start position. When the engine is running it sounds like the starter is still cranking. I tried tapping starter but did not help.

 

Sounds like a short to HOT.
So even with the starter relay pulled, the tuck will crank?
if so, pull the 7.5A STA relay the next time this happens.
we need to see what is supplying power to the starter relay.

 

It can be as simple as a shorted Solenoid. Even welded contacts

looking that would back feed into the starter circuit pin #3 would be hot at the starter relay. pin #5 of the relay is at system voltage always

In most cases this keeps cranking till the battery is dead or disconnected.

If it is not the solenoid only the wire off starter relay pin #3 being energized will crank the starter being the wire that energizes the starter solenoid

 

Correct.
the 7.5A STA fuse would also be hot.
if pulling that fuse kills power, we know the short is down stream of the fuse.
If not, its up stream or on the starter solenoid leg.

 

i appreciate the input and will check things out tomorrow and post what I find out. I have been really busy the last couple of days, but tomorrow my truck is priority #1. Thanks for your thoughts on this. a couple days ago I thought I was going to need a Priest, the way the truck was cranking and the key being in my pocket lol.

 

Do not rule a Priest out just yet in case that is your last resort.

Good luck!

 

I pulled the 7.5A STA fuse and touched cable to pos battery post , engine cranked w/key out. I pulled the starter, picking up a new one today.

 

I bought a new starter and put it in, the problem appears to be fixed. Shout out to TnShooter for all the help and information that got me back on the road. I learned alot from this experience. PROBLEM: a short in the starter/solenoid FIX: replaced starter and solenoid.

 

Nailed that one!!

Glad it was a easy fix.

I would have loved to take that apart and see just what happened.