Won't Start - checked these things - ECM suspected?

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I do not have a test light, but I do have a multimeter. I was able to disconnect one (broke one side of the hold down because the plastic is very brittle). I put a jumper wire across the two terminals, put an alligator clip lead from there to the positive side of my multimeter, then grounded the other side to good ground. Cranked the engine. The meter went to 12 volts. Meaning, I am getting electric flow to the injectors.
I have no fuel gauge and can't find the connector on the fuel rail anyway. Thanks Neil.
Take Care, Sharon
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very good thing to do (may have smoked the injector drivers). Even installed the way I described, a mechanical volt meter would probably not be able to respond to the injector signal fast enough. I had no doubt that you had voltage supplying the injectors, you proved that when you checked voltage to the red wire going to the fuel pump relay since that is the exact same circuit that the EEC relay switches on to power up all the various driven devices in the system. What needed varification was whether the injectors were being signaled -by- the engine computer, the easiest down and dirty way to do that is to substitute a light bulb in place of the injector. If you'd have mentioned that you didn't have a test light, you could have been directed to scrounging one of the vehicles side marker lights to use as a substitute. Since I know for a fact that a side marker bulb only draws 1/4 amp, this would have facilitated a safe test method and it would have only been at the expense of an (temporarily)inoperative side marker. If you don't have a tool to do a test with or are unclear on how we're describing to hook it up, please, please, please, stop, post back for clarification or for a way to fabricate or substitute. You can't begin to imagine how easily the integrated circuits can be fried inside the engine computer by performing a test wrong or by substituting a different piece of test equipment.

Can you borrow one from the AutoZone store?
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LOL! I give you and Thomas a lot of credit for sticking this one out as long as you have, but I think you may have finally met your match. Good luck... You're gonna need it. Ford builds a pretty bulletproof PCM, I guess we'll find out how good they protected the injector drivers... or not. Bob
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Agree, 100%

Bit of a paradox, no? She's been wanting to suspect the processor from the beginning, now we may never know...
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wrote:

I've observed people do her "little jumper trick" out of ignorance before...............and the processor survived. So.................we may still have an ending to the story.
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Bob, I concede. I don't think she let the smoke out of the box, but this is some one that logic defies!

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is some

She may not have but it wasn't for a lack of trying. I see at one point she jumped the tan/lt green wire to power also. I've seen this kind of thing all too many times. Someone who is trying to save a buck by doing car repairs themselves winds up bringing it in 'cause they finally gave up. Now they have not only the original problem but several others caused by the work they've tried to do. Usually not a good deal for them. Bob
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Yea, they cry poor, don't have money. When in reality have quite a good income and can easily pay for the correct repair the first time, but now have at least double the bill.

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??? A voltmeter has high resistance. The higher the better, in fact. Suppose it was 1Mohm (it's probably more than that). The maximum voltage it could be seeing is about 14V. So Ohm's Law tells us that at most there could have been 14/1000000A (14 microamps) flowing. Any semiconductor that couldn't deal with that much leakage current in any direction has no place in an automobile.
An *AMMETER* has low resistance, yes.
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The meter isn't what made the short.

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It was not the meter that did any thing, but the jumper wire. If that is what she did. She has a habit of being very inconsistent in what she says. Very troll like.

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what
troll
======================Hmmmm.......
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snipped-for-privacy@larwe.com (Lewin A.R.W. Edwards) wrote:

Re-read Sharon's description of *how* she connected the voltmeter to the injector plug. She didn't describe putting each test lead to each side of the circuit, she described connecting a jumper between the two terminals in the injector connector -then- connected the VOM between the jumper and a ground point. (about as unorthodox of a method of using a voltmeter as I've ever encountered) Since you're a fan of Ohms law, solve for how many amps went thru the injector driver when voltage equals 12.7 and resistance equals zero (or very near). ;-)

Yeah, so?
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wrote in message

That is normal, when the voltage goes through it's load, i.e., the coil of the relay and the circuit is grounded, you get 0 volts. If the ground circuit was open, you would see 12 volts, because it is not a complete circuit. When you see that the circuit is ok.

By making a ground, you are completing the circuit, energizing the relay, you will see 0 volts.

Then the relay is bad or wrong. Or the ECM is making ground all the time. Release the tab that holds the tan wire in the relay socket to make sure the wire is not broken at the terminal if that is ok put it back in the socket and one more test. With the relay in it's socket, cut the tan wire in a place you can splice it back together. Turn the key to run, and see if you have 12 volts. ) 0 volts still means bad or wrong relay. Did you check the resistance on the relay?

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Hi Sharon, Check your e mail @ no.com addres I've sent you a test instruction for the distributor module. The hotwiring of the pump is Ok just for test purposes. It would be a very dangerous way to drive the car in public hotwired in the fuel pump system. It is designed this way in case of a crash or fuel line rupture so if the fuel rails loose pressured the engine stalls, the pump will stop running. Due to no pulses from the module in the distributor. So If your module is bad, the car will run hotwired as you have proved out within these test instructions from everyone in this forum. If you drive your car with the fuel pump hotwired and have a crash and fatal fire, you have it right here in writting NOT to drive this car in this condition. The switch/breaker in the trunk is an extra measure of safety. Replace the module in the distributor. That will solve the problem. Have you ever noticed the fuel pump keep running when your car stalled..? I don't think so... Oh, OK...Just got your mail, and you've got it in the bag now...Just posting so others know... Regards, BeeVee

OK, I looked at the diagram, at the relay. Using a12 volt test light. Yellow wire- should have 12 volts all the time, check it while cranking the engine too. If it does have 12 volts all the time, remove the relay. With a jumper wire, jump from the yellow to the orange wire. The pump should run and the car should start. Please dont say cranks over if you mean running. Cranks is the starter cranking the engine, starts is the engine actually running. If it starts, then say it runs or it starts. Sorry but it can get confusing. Post back with your results. Maybe if we do this one step at a time we can firgure it out.
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I don't think anyone has suggested that she drive the vehicle with the fuel pump relay by-passed.

Um, no. The fuel pump relay does what any relay does, it allows for switching a high load circuit without running heavy gauge wiring and it allows for control of the fuel pump according to whether or not the engine is running. The relay in and of itself has nothing what so ever to do with crash worthyness.

No. If the "module" is bad, the car won't run, plus, there is no fuel pump running (prime) when the key is first switched on before the starter is engaged, the fuel pump should at least be able to prime regardless of whether the 'module" is working correctly or not.

Oh please, what is it that you think the fuel pump relay can magically do in the event of a crash?

Finally, a correct statement.

Why? If she jumpers the fuel pump circuit the engine will run. That proves that there is a PIP signal to the ECM which can trigger the ignition module -and- pulse the injectors. IOWs, she'd be wasting $100 on a part that for all mortal purposes is functioning correctly.

The problem does not manifest itself as a lack of spark or a lack of injector signal, both of which would be key functions of the ignition module. She has (for whatever reason) a fuel pump that will not turn on, even during the prime sequence which is totally separate from the ignition module.

Have you ever noticed that to energize the fuel pump on any domestic Ford product, all one needs to do is turn the ignition switch to the on position; the pump will run for at least two seconds. I didn't think so.
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wrote:

hotwiring
the
the
everyone
fatal
stalled..?
=================================I've got to back up Neal, he's right on the money. It is a power, ground, and or ECM problem. I would hotwire that pump if I *had to* in a second. But I would not make a habit of it, it definitely should be fixed. :)
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the
It does drop down a little while trying to crank the engine. I am going to try the next test anyway.

wire,
No, it will not start. The pump turns on, I can hear it, but the car will not start.
Take Care, Sharon
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wrote in message

to
and crank engine. Does the 12v light come on?
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Thomas,
After reading all that I have done and following this through from the beginning. Can you give me some idea of the different auto parts that you find suspect or that may be causing this?
Thanks and take care, Sharon
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