Topic: Truck wont start! please help!

[86turboyota]

Yeah,the key needs to be on. If you have no check engine light check the EFI fuse and check for power at the EFI fuse. Theres something up there. No check engine light leads me to beleive no power turning on the PCM. MIke

the on position but dont start it right?   EFI fuse is good, ill check for power there this weekend.  Sorry buts what the PCM?

[85oldschoolpickup]

1986 toyota pickup 4x4 sr5, 5spd, 22-re unknown mileage.

The truck wont start.  I have tried many things and at one point it was starting and running for about 5 secs then dieing, then i tried this fuel pump check thing ( http://www.4crawler.com/4x4/CheapTricks/index.shtml#FuelPump  scroll down to the fuel pump tricks) and i think i screwed it up worse ( now that i looked at the site again i think i may have jumped the wrong connector and fried something, but i dont know what) because now it wont start at all, still turns over but wont start, and the fuel pump wont turn on.  I know the pump is still good though because i hooked a wire to it from the battery so i could bypass everything and see if it was still good, and it is.  PLEASE HELP ME

if i was u i would check all the fuel lines and spark make sure the fuel line into the carb or ur fuel injectors is spraying fuel before u do anything because u definetly have a spark or fuel problem if that doesnt work check ignition coil and distributor.  Most importantly though check the fuel pump first u can check it by having someone turn the key to the on position and listening by the gas tank to see if u hear it come on and what i also like to do is start from the fuel lines around the gas tank disconnect them and crank the engine to see if it squirts.

[86turboyota [OP]]

if i was u i would check all the fuel lines and spark make sure the fuel line into the carb or ur fuel injectors is spraying fuel before u do anything because u definetly have a spark or fuel problem if that doesnt work check ignition coil and distributor. Most importantly though check the fuel pump first u can check it by having someone turn the key to the on position and listening by the gas tank to see if u hear it come on and what i also like to do is start from the fuel lines around the gas tank disconnect them and crank the engine to see if it squirts.

the problem is that their is no power going to the fuel pump, the pump is good but is not getting power.

[toymech]

The computer that runs the fuel injectors. If theres no power there you wont get injector pulse or power at the fuel pump

[RABIDYOTA]

ttry swaping ecus with you'r turbo. just make sure all you'r jumper wires are removed.

[MyBee]

Check or swap the fuel pump relay behind the ECU and also you might want to check the bulb of the check egine light maybe it is shot thats why it is not on. Happen to my runner once and I had the same situation.

[86turboyota [OP]]

ttry swaping ecus with you'r turbo. just make sure all you'r jumper wires are removed.

will the turbo ecu make my non turbo truck run?

[86turboyota [OP]]

Check or swap the fuel pump relay behind the ECU and also you might want to check the bulb of the check egine light maybe it is shot thats why it is not on. Happen to my runner once and I had the same situation.

already tryed swaping the fuel pump relay.. ill check the bulb saturday

[86turboyota [OP]]

The computer that runs the fuel injectors. If theres no power there you wont get injector pulse or power at the fuel pump

can i just use a check light to see if there is power getting there?

[86turboyota [OP]]

ok today i spent several hours trying the get the truck to start.  using a check light i confirmed that there is no power getting the the ign fuse.  i also discovered that there is no power getting to the coil/ignitor, so i ran a hot wire to the coil/ignitor and got the fuel pump to come on when i tryed to start the engine.  However we also figured out that the started solenoid doesnt seem to be engaging properly, which is also preventing the engine from turing over properly.  SO what i need to figure out is why there is no power going to the ignition system and why the starter solenoid is not engaging......  please help.

[Plowking]

Do you have a good ground? cleen up all you ground connections, check fuse connections as well mainly the underhood ones

(Check them fuses with continuity meter or voltage meter.

[BigMike]

Wow, sucks that I have been gone for so long.

#1. You will never get voltage to your fuel pump until you get +12 volts with the ignition ON circuit. This power comes from the AM1 fuse entering the ignition through a Black-Red wire and leaves along the large White wire and White-Red wire. The White-Red wire is the main ON power source for the entire EFI system. On the front side of the ignition (the input) check that you have a constant +12v on the Black-Red wire regardless of key position. If there is power there, but no power on the White-Red with the key in the ON position, then you've got a bad ignition. If you do not have power to the Large Black-Red wire, then you've got a problem between the fuse box and the ignition. Check the large 80Amp fuse with the plastic inspection window.

#2. If I may be picky, there is no such thing as a Fuel Pump Relay. The Fuel Pump is ran through the Opening Circuit Relay which receives its power via the same White-Red ignition ON wire. I am sure that after we establish power throughout the EFI system when the key is in the ON position, that the OCR will be working just fine. FYI it is only activated by the computer from the grounding signal from the AFM (Positive Air Flow Condition).

I am trying to remember how the starter signal wire gets its power. I know there is a large White wire that enters the Ignition along with the Black-Red wire, but I am not sure which one the Black-White starter signal wire gets its power from. If it gets its power from the Black-Red wire, then, since the starter is working, that must mean that the AM1 fuse is OK and you should have input voltage to the ignition when the key is turned ON.

So please verify that the White-Red wire leaving the Ignition has +12v with the Key in the ON position.

The truck will NEVER run unless the check engine light comes on with the key in the ON position and the engine RPM is below 250 rpm. You do not need to tear the whole dash apart to check the Check Engine light bulb. Just go to the computer, and I believe it is the middle plug, you will find the only Violet wire on the entire truck. This is the Check Engine light circuit. You will need to Ground this wire to turn the Check light on, BUT! at the same time, the Instrument Cluster must have its own voltage, which it gets from the same White-Red wire that is powered in the ON position.

Unlike all other light bulbs in the instrument cluster that have a constant (short) ground and an open power source, the Check Light bulb has a Constant (short) power source and an open ground. So other lights, like the high beam light, can be tested by simply running +12v to it, but the Check Engine light is backwards.

So it all comes back to the simple fact that we must have +12v on the White-Red wire when the Ignition is in the ON position.
You can not check if the Check Engine light works unless that circuit has voltage running across it.

Let us know
Mike

[86turboyota [OP]]

Well thanks to your insight  bigmike    we bypassed the ignition with a hotwire and got the truck to start, proving that the ignition is faulty.  So now that i got the truck to start im gonna yank the engine and put it in my 4runner 
thanks everyone for your help

[toymech]

 Its possible the actual ignition switch has failed,may actually be that simple. Do not put a regular test light on the injectors,youll burn up the computer. You need what is called a noid light which is a resistor and test light to save the computer from a voltage spike. Please E-mail me if you have any questions. Ill be glad to help.  Mike