Driving down the road, hit a pretty good size bump in the road, and the truck immediately shutdown. It will turn over but will not start as if it is not getting any fuel. Any help is greatly appreciated.

 

This is on a 1991 toyota pickup v6

 

Well, stay away from good sized bumps!

Welcome to YotaTech. There are hundreds of places where a broken connection (caused by the bump) will cause a shutdown.

Assuming "immediately shutdown" means immediate, I would check ignition first. (lack of fuel should give 2-3 seconds to shutdown as the rail pressure bleeds off). Get your timing light (about $30), and put the inductive pickup on any plug wire. Crank the engine; if the light flashes you have spark.

To check fuel, get your multimeter ($8) and measure voltage to ground from B+ on the diagnostic connector. You should have battery voltage (about 12.6v) with key-on. Jumper B+ to FP, and you should hear the fuel pump start. If your truck will start WITH the jumper in place, you have a problem in the VAF-COR circuit.

Let us know what you find.

 

Start at the battery cables and work your way from there.

 

Do as Scope says ^^^, AND Please put us at your truck. What else do you not see, hear, feel, smell now that you do when truck was working properly? It will help narrow down where to look.


Starter is cranking (turning over), so there is strong battery power and block ground to starter and to fuse block which supplies cranking control circuit.

 

after I hit the bump it could have been a few seconds before the engine died. Everything else still works, lights radio, wipers, etc, so not battery issues. it will turn over just not crank. Like scope103 suggested i'll start with the jumper on B+ to FP and see what happens. The VAF-COR is in the throttlebody?

 

Vocabulary! To most of us, "turn over" and "crank" are basically the same thing. It sounds like your engine will turn over but won't fire at all. You can pick out any words you want, but try to make them descriptive.

That's one way to think of it; to me, it sounds like hardly anything works! That's why you use a multimeter https://www.harborfreight.com/7-func...ter-63759.html (did I say $8?) to measure the voltage at B+. If you don't have battery voltage there, you can listen to your radio all day, but the engine can't run.

 

I did not have power to the fuel pump with the key on, so I jumpered the B+ to the FP in the diagnostic box to bypass the Open Circuit Relay
and the fuel pump did kick on. My question is should the truck have been able to start? Mine did not. What would be my next thing to look at?

 

Air/Fuel, spark and compression are all needed at the right times and quantities to make an internal combustion engine run.

You've verified the fuel pump comes on when bumpered in the diagnostics port, but do you smell fuel in the exhaust pipe?

Did you test the spark as mentioned above?

 

You're not supposed to. The COR is closed with the key to STArt, then once the engine starts a switch in the VAF closes to keep the COR closed. The test you did bypasses the whole VAF-COR circuit, so it is often recommended.

As a further (easy) check on the fuel system, I'd replace the fuel return line from the FPR with a 6mm (1/4") clear vinyl tube to a suitable container. Start the fuel pump with your jumper. There's no spec for this, but I get about 1/2 liter/min through the fuel return. If you get nothing, your fuel pump may not be delivering enough pressure.

(You use the fuel return line because it is low pressure and you can just put it back on when you're done. If you remove any high-pressure line, you MUST replace the crush washers.)

 

Check the EFI fuse under the hood (check all other fuses too if you haven't already) . If its popped, its possible your O2 sensor wiring is rubbing on the heat shield.