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

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If any of you have not been following, here is the situation. I have a 1988 Mercury Grand Marquis, with 93,000mi that I just drove close to 3000 miles
across country with absolutely no problems. A few days after arriving here, the car wouldn't start. I replaced the battery (twice) and the EEC and fuel pump relays. Still no start. I am trying to decipher the posts here to check things out further. I am systematically going through each suggestion here starting with the obvious ones first:
1) I have checked the inertia switch ('crash switch), it is okay and functioning properly. 2) I sprayed starter fluid in the air filter passageway to the fuel injector housing. Car starts up great, then stops. 3) I 'hotwired' the fuel pump (added extra ground from the tank to frame to be safe), pump kicked on okay. 4) I have now checked for spark by using a screw driver in the spark plug wire. It sparks well (not weakly). 5) Checked all wires going to the relay for insulation breaks, found one small one, replaced with electrical tape. 6) Checked the wires going from the fuel pump relay, through the inertia switch, to the fuel pump by hotwiring that circuit only (small pulses of juice). Fuel pump turns on.
The wiring diagrams that I am using (matches my relay wires) are here:
http://www.rare-cancer.org/car/relaywire.gif
If I have done the ECM test properly (following Thomas's suggestion), then the ECM may be the problem. I hooked a jumper wire into the socket of the tan/lt grn wire of the relay. I DID NOT jumper the yellow to orange wire (see link above) sockets. I attached the jumper wire to the hot side of my multimeter and grounded the other side. I cranked the engine over. I did not get any reading with the multimeter setting at 10. Could someone tell me if I am doing this right?
Thank you and take care, Sharon
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addendum per Stan's suggestion:
I put the fuel pump relay back in it's socket, used my multimeter to test the tan/lt grn wire for any movement when I turned the key in the 'run' position (not cranking). Flatline, it never moved.
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The relay must be installed to measure the voltage on the tan/lt grn wire. Was your multimeter set to ohm's or DC volts? Stan
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Stan, just to let you know, the insulation was bad on the red wire in the beginning. That wire is reading fine on the DC setting of the multimeter. Thanks, Sharon
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[snip]
With the ignition turned on, do you have 12 volts at the red wire going to the fuel pump relay? (There should be)
if so
If you ground the tan/lt green wire at the the EEC self test connector, does the engine run? (this will mimmic what the ECM does to ground the fuel pump relay, which is; pulls that side of the relay winding to ground)
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Yes there is +12.

pump relay, which is; pulls that side of the relay winding to ground)
I actually stripped the insulation off of the tan/lt grn wire to get a good connection for the alligator clip. I clipped the other side to the ground at the self tester. Car will not start. Cranks, but no gas. I even tried inserting a bare wire into that ground connection to make sure I was getting a good metal to metal connection. Still, no start. There are already two wires that are tan lt/grn coming into that tester. I would think they make the ground ok. I am going to try one other thing. Nope, that didn't work either. I tried grounding the ground off the self test plug. Just to make sure IT was grounded. Then I tried doing a straight ground off the tan/lt grn wire on the relay. Still nothing.
Any other suggestions? Thanks for helping. Take Care, Sharon
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Sounds like either the red wire or tan/lt grn wire is not conected to the relay. It could also be a bad relay but I don't think so. I would test the relay just to be sure it is good. Take the relay out of the socket and put +12 volt on the conector that would go to the red wire and then ground the conector that would go to the tan/lt grn wire and it should click. Stan
wrote in message news:nonelson->

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Okay, in a round about way, you did connect the tan/lt green wire to ground as i directed. This -should- have forced the relay closed and turned on the fuel pump.
How does the new fuel pump relay compare to the old one physically? Is it the same shape, same color, same terminal configuration? Is there a Ford part number on it, is it the same as the old relay? If you look at the terminal end of the new relay, do you see any numbers that identify the terminals, numbers such as; 85, 86, 87 30, 87a, ?
I'm thinking that AutoZone sold you the wrong relay, you have power to the primary (red wire) you by-passed the ECM when you grounded the tan/lt green, you can make the pump run by jumpering the secondary, so the only thing left is that the terminals in the relay connector aren't properly matching the terminals on the relay itself. Two seconds (or so) after you turn the key on you should be able to measure 12 volts at the tan lt/green wire, you can take the measurement anywhere in the circuit, at the relay itself, at the EEC self test connector, from your posts so far, you haven't seen 12 volts at the tan/ lt green under any circumstances when the key is switched on, this means that the 12 volts on the red wire are not making their way thru the relay coil windings, either because of an open in the windings or because the terminals don't match up.
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No, it is not. There are more terminals on it (5 vs. 4) and it is black and grey, but it is the part number that both PartsAmerica and AutoZone show for my car and cross reference to the old part number.

I couldn't agree with you more, that is why I took the original 'new relay' back to AutoZone and went through all their info. They swear that the extra terminal is not used.
Take Care, Sharon
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I'd have a lot more confidence in that relay if it came from a NAPA, CarQuest or from a Ford dealership. Autozone, Parts America and other such bubble pack palaces tend to sell offshore third world built junk which often times does not work correctly out of the box. The only way to know for sure if that fuel punp relay is correct would be to pry off the cover and physically trace down the terminals to their respective contacts and coil windings.

Sounds like a version of the Bosch ISO relay which is somewhat popular for certain automotive applications, it has five terminals, two for the coil winding, one hot, one normally closed, one normally open. If the terminals were numbered, it would be pretty easy to direct you as to which colored wire should go to which terminal.
Some testing which you can do in the morning, weather permitting...
voltmeter negative (black) lead connected to battery negative, relay unplugged from socket; Yellow relay wire reads 12 volts always (it should) Red relay wire reads 12 volts with key switched on (it should) Jumpering the yellow wire to the orange wire, the car starts and runs (it should)
Switch your meter to ohms or continuity test; red lead on (touching)the tan/lt green wire at the relay socket, black meter lead on (touching) ECM connector harness terminal 22, meter shows low ohms or continuity (it should).
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running? Does the pump ONLY run when you hot-wire it? It sould run for a few seconds when you turn on the key. Then it should run when cranking.....Is this the case?


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clarification, did you try to start it when you knew the pump is

Yes, I did crank it over Scott (after I knew the pump could run hotwired). It will only run hotwired, actually. Thanks, Sharon
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I just went out and tried to start the car, several times. Then I went to the self test connector and hooked it up with a paper clip. No flashes of the engine light. So, even though this car cannot start, IT thinks it is just fine. LOL "A better Ford idea!" Thanks and take care, Sharon
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Bill
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Did you do the self test producers?

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Does the engine run and keep running when you "hotwire" the pump?

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I haven't tried that. Is it safe to try? I would be concerned that it would be getting a steady flow of gas instead of a pulsing flow Thomas. Thanks and take care, Sharon
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stays closed until you shut the engine off. Bob
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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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