west_89_

hey, i have a 94 pick up 4x4, 3vz-e. i was driving down the highway at 120kms an hour and was running fine. then the truck just died, i pulled over and try to start the truck. it wouldnt start at all. i found out i had not spark from the ignition coil so i replaced it. then tryed to start it, it started but then died about 3 seconds in. im unsure what is the issue now......... i check all the sparck plugs for damage they seem all in good condition. i have a brand new cap and rotor aswell. what is more likely that its my wires or the distributor? or something else? plz help!

scope103

Get a timing light. That's the easy way to see if you're getting a spark pulse (using a plug against the block is a little more comprehensive, just more work). Are you sure your spark is quitting after 3 seconds?

"Starts then quits after 3 seconds" is the classic sign of a problem in the VAF-COR circuit. It's very easy to determine; jump FP to B+. If the truck starts and runs you've narrowed down the problem considerably.

(If the truck runs with the jumper in, don't be a fool and drive around that way. If you get in an accident that breaks a fuel line, the pump will not stop. You'll be trapped in the cab being soaked with gasoline.)

west_89_

so it is getting spark all the way to the plugs..... it dosnt always go for 3 seconds. i was thinking it might be the pick up coils or the air gap on the distributor. would that not cause the truck to start becasue it gets spark still. but cause the truck to die becasue they are not acuratly detecting the camshaft and crankshaft positions? am i correct?

abecedarian

Typically, if it starts then dies within a few seconds, the AFM above the air filter is suspect- it controls the fuel pump when the engine is running.

Since you say it is starting, then dying without spark, that leads to a different issue.
Check the plugs around the distributor and igniter (near the ignition coil) for any moisture, corrosion, proper seating within the connectors, and such. Check continuity in the wires where possible.

west_89_

that is the mass air flow sensor your talking about right? is there any fuses conected to the mass air flow sensor? if so where are the locations im having issues finding info about mass air flow sensor.

scope103

http://www.ncttora.com/fsm/1990-1995...e/volumeai.pdf

"Volume Air Flow" sensor. Everything is easier when you use the right name.

The VAF grounds the COR coil to power the fuel pump. The STA (start) signal does the same when you are holding the key in the start position.

I've given you a clue for how to easily diagnose this.