Mechanics

PLYMOUTH VOYAGER FUEL PUMP PROBLEM

1996 Plymouth Voyager • 150,000 miles

My van quit running while driving down the highway as if it ran out of gas I poped the hood and sprayed a shot of starter fluid into the throttle body and when I cranked it up it ran for a short second so it was getting spark but no fuel I then assumed the fuel pump was bad and I changed it but now the van isn't getting any spark from the coil pack wich doesn't make much sense before I changed the fuel pump a little shot of starting fluid would make it run a second now after putting the new pump in I'm getting no spark now my best guess is the low pressure caused the automatic shutdown relay to cut the power to my ignition coil. What do u think it could be and how do I fix it now


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Bdudley86
March 19, 2013.



You have the right idea but that's not how the ASD relay works. The Engine Computer turns it on when it gets pulses from the crankshaft position sensor and the camshaft position sensor. That relay sends current to the ignition coil or coil pack, depending on which engine you have, the injectors, alternator field, oxygen sensor heaters, and fuel pump or pump relay. When the engine stops rotating, (or pulses stop coming from one of those sensors), the computer turns the relay off. That's to turn the fuel pump off if a fuel line got ruptured in a crash. That stops the pump from dumping raw fuel on the ground.

Chrysler fuel pumps rarely quit while they're running. That's how GM pumps typically fail. Chrysler pumps almost always fail to start up when you start the engine.

There's two places to start. First of all check for diagnostic fault codes. Chrysler makes that real easy. Cycle the ignition switch three times from "off" to "run" within five seconds without cranking the engine, then watch the numbers appear in the odometer display. The next thing is to determine if the ASD relay is turning on. Measure the voltage on the dark green / orange wire at the ignition coil or any injector. You should see 12 volts there for one second after turning on the ignition switch, then it must come back during cranking.

Based on your description of how it acted, I'm inclined to think the splice for all those dark green / orange wires is corroded and the fuel pump quit first because it draws the most current, and now the voltage is too low to run the coil. You might want to swap the ASD relay with a different one like it too just in case the contacts are pitted.

Caradiodoc
Mar 19, 2013.
Check the if the injectors and the coil being powered by the ASD relay thru the dark green and orange wire-

Rasmataz
Mar 19, 2013.
Well the thing that has me stumped is that the fuel pump is runing u can hear it kick on now when u turn the key as to before I changed it when the van broke down u couldn't hear it also there was no pressure at the fuel rail at the test valve before I changed it now after I changed the pump u hear It kick on and the fuel comes out the test valve now but since I replaced the fuel pump there's no spark at the coil pack when before it had fire because it would run on starter fluid and now its not even firing I didn't disconect the battery when changing the fuel pump maybe that has something to do with it. Also today I changed the crank sensor and coil pack I will check the code tomorrow and get back to you I just thought that maybe I tripped a fuse or something simple when changing the pump

Tiny
Bdudley86
Mar 20, 2013.
The pump circuit is dead when the engine is not rotating, even if the ignition switch is on so you wouldn't blow any fuses. Was there a thick paper spacer stuck to the end of the new crank sensor, or did it have a thin plastic rib molded onto the end? Those set the air gap which is critical.

The pump will always run for that one second when you turn on the ignition switch but when you don't have spark there's a 99 percent chance it does not continue to run when you crank the engine. That makes diagnosis misleading because you will appear to have fuel pressure. You'll also be missing the injector pulses.

I'm still thinking about how it ran for an instant on starting fluid. That almost seems to imply there are two different problems but that is unlikely. Check the fault codes and lets go from there.

Caradiodoc
Mar 20, 2013.