Our problem started 4 weeks ago. She got up to go to work and it wouldn't run. Fired up but shut down in a few seconds. I went home at lunch and fired it right up. Tested igniter,bad,installed another,after waiting days for it. Same day as sons graduation day ,ran to school and afew stops afterwards. next morning wouldn't run again.Installed coil,again after waiting on part to arrive. Ran til next morning .Called a freind to come over and help.After spinning vehicle over a few times battery went down. Put charger on it, longer it charged longer it ran. Swapped battery out of sons car fired right up. Next morning wouldn't stay running again.Ordered distributor no help. Now a circuit opening relay and a computer later still won't stay running.Have spark at plugs,have cold start injector,but no injector pulse using noid light. Tested injector wires found 12 volts to both terminals. HELP PLEASE We realll love this vehicle

 

Alternator? Have you had it tested? Sounds like it the alternator is going bad and the truck running is draining the battery until it dies as well!

 

Nope, Will do tomorrow at lunch. If can get a ride.

 

to test if you have a bad alternater you need the tester from MotorMite which you can go to your autoparts for it, it only cost around ten dollars, and yes it might of be the alternator, the battery have the power to start the truck up then the alternator will take over then if it shut down then it should be the alternator, I mean ALTERNATOR!...

 

When it dies and wont start, is it getting spark while cranking? Any error codes shown? As for the injector wire voltages. If you see a constant 12V on both terminals, that means its not firing. I assume your measuring this w/o motor running? The injectors are driven with a Pulse Width Modulated signal. Basically a square wave, whose pulse width determines the time the injector is fired. You really need an oscilloscope to look at the waveforms on the injector. But its never a constant 12V when engine is running. The ECU "swicthes" the ground to the injector to obtain this PWM siganl.

toyo22r@hotmail.com
95 4Runner

 

QUick way to check an alternater, Once running unplug the negative side of the battery, If engine dies, Need new alternater, Still running?, Turn lights on to (highbeem best), If engine dies, Need new alternater, Still running????, Also Turn on AC too, If engine dies, Need new alternater.
Best quick test there is.

 

Hey, all. Tested altenator checks out OK. Installed new battery anyway. New cable ends also. Still won't run. Tested fuel pressure too,44lbs. I also tried jumping FP@E1 terminals in diag connecter,Popped efi fuse. Any ideas and or suggestions would be greatly appresiated.

 

More info runner will stay running on carg cleaner. Not getting fuel to cylinders. Dies soon as quit spraying cleaner. Still searching. Will get running if not sent LOONEY BIN FIRST !!!!! thanks all

 

If your popping the EFI fuse when you short the FP terminal to E1 then i would say the fuel pump is bad. How long did it take for the fuse to pop once you shorted the connector? How were you able to measure the FP pressure?

toyo22r@hotmail.com
95 4Runner

 

Hello,Once again. Better news now though. Out of the dog house,wifes 4runner is a runner once agin. Thanks for all your help. Pinouts,suggestions and yota info in all your post and threads, new & old Now looking for a toy to call my own. Another 2nd gen I hope. MERK811

 

So what was the problem/solution?

 

Sorry bout that. just messin around. Apparently. when the distributor fried,the spike toasted the computer and air flow meter right along with it. Reman distributor, reman air meter and a used computer. All at one time hurt my pocket big time. Wife thinks i,m nuts for wanting my own. But I love a challenge. And she really loves hers !!!!!

 

Unplugging the battery is a good way to fry the computer. The alternator needs the battery to help smooth out the voltage. This is less of an issue with voltage regulated alternators. To check that the altranator is working a good quick check is to check the voltage with the truck off, and then start it and check the voltage. The voltage when off should be around 12.5v, and with the engine on it should be closer to 14v. If you want to load test it, take it to an auto parts store, and ask them to test it for you.