1997 TP no fuel pressure - Page 2

jackel440 · 08-08-2010, 05:57 PM

I probed at the ecm and still shows no voltage.
Now correct me if I am wrong ,but the only reason it would run on starting fluid was it was pulling it into the cylinder like a normally asperated engine.I had the pump running on a jumper and it will not run so the injectors were not working.
SO that is the conclusion of the reason of no firing of the injectors.I agree that the ecm does fire them by actuating the ground.
I don't believe there is any kind of secuirity on it.I no there is no aftermarket on it.
I also have noticed that the engine is a junk yard replacement and the ecm looks to be a junkyard piece also.It has the normal yellow grease pencil marks on it.

old_master · 08-08-2010, 06:14 PM

You are correct about the injectors. I misunderstood what you indicated a few posts back. Ok... with the ignition in the RUN position, the pink wire has voltage at the fuel pump relay, does the pink wire have voltage at the injectors?

The yellow grease pencil marks indicate junkyard, but it also points to the fact that someone else has been trying to troubleshoot this thing. That's why I'm having you check all of the basics. Rule of thumb in auto repair is "always assume the guy before you didn't know what he was doing."

likeamour · 08-08-2010, 06:27 PM

Quote:

Originally Posted by likeamour

Another thread hot wired the pump from the ignition in the run position.

From what I understood this Trans Sport ignition switch would NOT supply electricity to the fuel pump in the "start", but would ONLY in the "run " mode.

jackel440 · 08-08-2010, 06:30 PM

Ok well I went out and probed the all the pink wires and they all had voltage.LOL
There is a red wire and the green w/white under the area of the relay.This is whats crazy as the fuse box has a 3 plugs of wires just like would be on a firewall connector.But the wires done't seem to coincide with whats above them.I know the relay has 5 terminals ,but under it there is only 2 wires.I don't see the ground wire,the pump wire.Not very easy to figure out what is what.
I bought a haynes book ,but it's wiring diagram is not the best.
I did probe a pimk wire at a connector right by the coil pack which looks to be the loom going to the injectors under the upper plenum.It did have voltage there.
So now what would you like me to look at next.

jackel440 · 08-08-2010, 06:33 PM

Quote:

Originally Posted by likeamour

From what I understood this Trans Sport ignition switch would NOT supply electricity to the fuel pump in the "start", but would ONLY in the "run " mode.

I hot wired the pump,and it didn't matter if it was in the run or start position.It still will not start.I am getting fuel when hot wiring the pump,but the injectors will not cycle to let the fuel into the engine.
Seems to be an ecm issue with not starting the pump and cycling the injectors.

likeamour · 08-08-2010, 06:41 PM

Would a malfunctioning ECM give a code? Or it just thinks its right!

" The right is right, until the right is wrong. Then the left is right, and that is where we are now"

jackel440 · 08-17-2010, 05:15 PM

OK update.New ignition switch and still no change.Just cranks with no fuel pump or injectors.
I had the nieghbor come down with his new snap-on scanner ,and tried to communicate with it.Nothing from the computer to the scanner.That's why i put a new ignition switch in it.Hoping on the off chance that was the problem.
So now I am thinking I must have a computer.How can I verify that before laying out cash for one?
I am really hating this van.Thank goodness it's not mine.

likeamour · 08-17-2010, 05:42 PM

Try your computer in another Trans Sport (same year). We have found 2 for $400 and $700. May buy one, to fix the first, then resell them both at a small profit.

jackel440 · 08-17-2010, 06:27 PM

No other TP around here that I know of that I could do that with.
I checked the 24x crankshaft position sensor on the front of the engine.It showed voltage and cycled on and off like it is supposed to.
I found in another thread that it and the ign. module could cause the no injector fire and possible no fuel pump.
I might have to let the owner take it to a real service shop

to work on it as I just don't have any more time to mess with it.
I am still thinking it is the computer,but not positive.

old_master · 08-17-2010, 06:33 PM

Before spending any money, check terminals 4, 5 and 16 (Signal ground, chassis ground, and battery voltage.) in the connector under the dash with a digital volt meter. Usually when they don't communicate you'll find the problem here. Most of the time, ECM's are replaced due to misdiagnosis, (they're pretty much bulletproof).

jackel440 · 08-17-2010, 07:10 PM

Quote:

Originally Posted by old_master

Before spending any money, check terminals 4, 5 and 16 (Signal ground, chassis ground, and battery voltage.) in the connector under the dash with a digital volt meter. Usually when they don't communicate you'll find the problem here. Most of the time, ECM's are replaced due to misdiagnosis, (they're pretty much bulletproof).

Ok i have .5 ohms on the signal ground and the chassis ground.I have 10 volts at the battery voltage pin .Checked the battery and I have just at 12 volts.I need throw a charger on it again.It still cranks fine though.
Did I check that correctly?
Atleast I am getting power to the plug.Still need to see if it will comunicate with a scanner though

old_master · 08-17-2010, 07:52 PM

.5 ohms from pin 5 to ground and .5 ohms from pin 4 to ground, perfect. Pin 16 should show battery voltage. If you're showing 10 volts at pin 16 and battery at 12 volts... I'd say there's a poor connection somewhere.

jackel440 · 08-17-2010, 08:00 PM

I agree I should pull the cables and clean them good and then look for any other bad connections.
I am going to call my nieghbor and see if he can bring his scanner back down,and see if it will comunicate now.
I really need to pick up a good scanner to have here,and not one of those crappy autozone specials.Maybe an updated used snap-on or something.
Alright Old-Master what do you think I should check into next?

old_master · 08-17-2010, 09:48 PM

Better go back and double check the resistance and voltage as described in post #3. With the relay unplugged, the green with white tracer wire at the fuel pump relay must show battery voltage to energize the relay. Check it at the ECM too, must show battery voltage for 1 to 2 seconds when you turn the ignition to the RUN position, then it will drop to zero volts. It should show battery voltage continuously in the START position.

jackel440 · 08-18-2010, 04:16 PM

Quote:

Originally Posted by old_master

Better go back and double check the resistance and voltage as described in post #3. With the relay unplugged, the green with white tracer wire at the fuel pump relay must show battery voltage to energize the relay. Check it at the ECM too, must show battery voltage for 1 to 2 seconds when you turn the ignition to the RUN position, then it will drop to zero volts. It should show battery voltage continuously in the START position.

I am not getting battery voltage at the green w/white tracer at the relay or from the wire back probed at the ecm.
My nieghbor is going to come back and try to get his scanner to comunicate with it again this evening sometime.

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