1997 TP no fuel pressure

[jackel440]

I am working on a friends van,and I am in need of some advice on what to do for it.
I am a mopar guy so I am at aloss working on this van.Her is what I know
Van was drove to gas station.filled up the tank.When she went to start it it would just crank.I came and towed it to my shop.I checked the fuse on the fuel pump circuit and all was good.I could feel the relay kick.I proceeded to pull the tank and the pump wouldn't run.
I ordered a new pump assembly and installed it.Now she has a working fuel level guage(which did not work before).
I went to start the van and now the pump will not run at all.The engine cranks fine,and I pulled a plug wire and I do have spark.There is no check engine light.
So I have cranking,spark ,but no fuel.
I have no manuals or schematics to trace what goes where on the van.I need to figure out why I am not getting power to the pump.Any help[ would be greatly appreciated
Thanks
Aaron

[jackel440]

Ok I was out trying to investigate further ,and I did find a blown 10 amp fuse labeled"ECM Sense" I replaced it then tried the key.I then got the pump to kick on and off for a second.
Still no start though.I then turned the key back off and then on and Still no pump coming on just like before.The fuse is still good that i replaced.All other fuses are good.So I am at a lossat the moment.
I shot a squirt of starting fluid in the breather and it would try to fire.
I put a jumper in the pump relay and had the pump running and then tried to start the engine.Still wouldn't run.I am wondering if the pump and injectors are on the same circuit or control?Maybe the reason for the pump not coming on is a communication problem from the injectors?
I so wish I had a scan tool in my shop.As this guessing crap on how things are tied together sucks.
ANy Ideas anyone?

[old_master]

At the fuel pump relay, with the relay unplugged:

Pink wire, from "INJ Fuse" 15 amp: battery voltage at all times.
Black wire, relay ground: less than 5 ohms to ground at all times.
Green with white stripe wire, relay trigger from ECM: Battery voltage for 1 to 2 seconds when ignition is turned to RUN position, and battery voltage continuously with ignition in START position.
When the relay is connected, the grey wire, (goes directly to the fuel pump) should have the same results as the green with white stripe wire. Grey wire at the fuel pump module connector should also have the same results. The black wire at the fuel pump module connector must show less than 5 ohms to ground.

What brand of fuel pump did you install?

[jackel440]

The pump is a Spectra premium replacement pump.I know it is not a factory pump,but thats what the owner could afford.I purchased it through Rockauto for her.
I do have battery voltage at the #5 pin of the relay.I pulled the fuse box loose to try and find the wires on the backside and when I probed what I though should have been hot wasn't.
I will have to check the wires you listed tomorrow after work ,and see what I can find out.
I might try and pick up a relay just for giggles to see what happens.I know the pump did come on once for the priming cycle but it was intermitent when it did.
I just went out and checked the harness connector going into the floor ,and it was in great shape.No contact problems there.
aggravating to hit the key and it just cranks but no fuel pump.

[old_master]

Something about the aftermarket fuel pumps, lots of problems with noise, intermittent operation, leaking check valves, insufficient maximum output, and usually a short life span. If you don't mind all that, and changing the pump every few months, or in this case, a few hours, doesn't bother you, then they're worth it! Keep us posted as to what you find. If you have any questions, just ask.

[jackel440]

Thanks for the reply and the welcome info Old Master.
Well I have used several aftermarket pumps and had good luck in the past so we shall see what happens.
I have a lift in my shop so changing it out for my friend if does puke will be no big deal.I do know though that If I can't get power to the pump it won't matter much anyways.LOL
I will let you know what happens tomorrow

[likeamour]

Have similar problem at our garage. I've learned if oil pressure sensor is not sending signal the computer cuts out the pump.
Junction of three wires behind the passenger light that corrodes and cuts the circuit.
Open orange and red wire by the driver shock tower supplies power to the fuel pump by connecting it to the positive.
Cut out switch corrodes in the full throttle position at throttle linkage end.
Good luck.....

[old_master]

Originally Posted by likeamour

...I've learned if oil pressure sensor is not sending signal the computer cuts out the pump.
Junction of three wires behind the passenger light that corrodes and cuts the circuit.
Open orange and red wire by the driver shock tower supplies power to the fuel pump by connecting it to the positive....

The oil pressure switch supplies an additional path for current to flow to the fuel pump when oil pressure is above approximately 7psi. It will not disable the fuel pump if the oil switch fails. The orange wire feeds both the oil pressure switch and the fuel pump relay. The red wire at the fuel pump relay goes through the relay and directly to the fuel pump ONLY when the relay is deactivated. The red wire is called "pump prime" and is used only for diagnostic purposes. The wire dead ends, usually within a few inches of the relay.

[likeamour]

So it may be the cutout switch at the end of the throttle linkage.
Another thread hot wired the pump from the ignition in the run position. Consequently he changed the ignition switch ( $13) to fix the problem.

[old_master]

Originally Posted by likeamour

So it may be the cutout switch at the end of the throttle linkage.

The fuel pump runs continuously when the ignition is in the START position. It will also run continuously in the RUN position, provided the ECM is receiving a signal from the crankshaft position sensor. If the throttle is held wide open when the ignition is in the START position, the ECM shuts off the injectors but the pump will continue to run.

[jackel440]

I installed the new relay ,but no dice.I we pulled the relay out and I have the constant voltage from the pump fuse.I then had the key cycled on and checked for voltage from the ecm to trigger the relay.I got no trigger from the ecm on the sockets in the fuse/relay holder.
I have the box unbolted and flipped over and the wires under the box don't seem to correspond with the earlier post.I only have a green with white tracer going up to were the relay is.I assume this is the ecm trigger wire?I fail to see a gray or black wire under there fo the pump or ground.There must be a circuit board between the wiring plugs under the fuse box and the top were the relays plugs in.I also have about 10 or 12 pink wires under there so that is confusing.
Now what should I be looking at to see what is causing the no signal to turn on the relay?
I also did check the pressure of the pump when I jumped the relay and it put out over 40 lbs.
So now what?
thanks

[jackel440]

I traced down all the wires on the ignition switch and checked for voltage and the switch harness checks ok.I have no signal from the ecm to turn on the fuel pump relay,and I do not have any signal to the injectors.I installed the relay with a jumper on the signal from the ecm to the battery ,and the relay came on then tried to start the van.All I get is cranking with no firing.I have good spark.I then tried shooting ehter in the intake and it would run on ether.So conclusion is I have no injectors working either.
Now what would cause the injectors and pump to not work?
PCM? Sensors somewhere on the engine?

[old_master]

The green with white tracer wire only has battery voltage for 1 to 2 seconds when the ignition is initially turned to the RUN, (not START) position, then it drops to zero volts. Before rechecking, turn the ignition off for at least 10 seconds to allow the ECM time to prepare for the next cycle.

The 1 to 2 second time frame is called pump prime. It allows the fuel pump to bring the fuel system up to operating pressure. If the ECM does not receive a signal from the crankshaft position sensor during pump prime, (which it won't because the crankshaft is not turning) the fuel pump relay is deactivated.

With the relay unplugged, turn the ignition to the START position, if you probe the five terminals in the socket, you should show battery voltage on two terminals: The pink and the green white tracer wires. Post your results.

The pink wire feeds the injectors and the pump. The injectors should have battery voltage in the RUN and START positions continuously. The ECM supplies ground to fire the injectors.

[jackel440]

Originally Posted by old_master

The green with white tracer wire only has battery voltage for 1 to 2 seconds when the ignition is initially turned to the RUN, (not START) position, then it drops to zero volts. Before rechecking, turn the ignition off for at least 10 seconds to allow the ECM time to prepare for the next cycle.

The 1 to 2 second time frame is called pump prime. It allows the fuel pump to bring the fuel system up to operating pressure. If the ECM does not receive a signal from the crankshaft position sensor during pump prime, (which it won't because the crankshaft is not turning) the fuel pump relay is deactivated.

With the relay unplugged, turn the ignition to the START position, if you probe the five terminals in the socket, you should show battery voltage on two terminals: The pink and the green white tracer wires. Post your results.

The pink wire feeds the injectors and the pump. The injectors should have battery voltage in the RUN and START positions continuously. The ECM supplies ground to fire the injectors.

I did check for the voltage during the pump prime nothing there.I checked several times.
I only have voltage on the socket supplying voltage from the pump fuse.I pull the fuse and that socket goes dead.I believe it is the #5 pin
The #3 is the feed to the pump if I remember right.
I pulled the cover from the ecm and checked for a signal from the ecm according the diagram and did not get any flashes whatsoever.
Where should I look to check for voltage to the injectors?I will go back out and look to see if I can see which pink wire is the inj.feed.
I am thinkn i might have a bad ecm now ,but not positive yet.

[old_master]

The same pink wire feeds the injectors and the fuel pump relay. Labeled FP/INJ 20 amp fuse. We need to get voltage on the green white tracer wire, that's where the problem is. Try probing the green white tracer wire as close as possible the ECM. See if it shows pump prime there.

Just a thought.... does this vehicle have any kind of anti-theft device on it, factory or aftermarket?