Still Won't Start

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I get a reading on the one that is the "always on" connector when I put the key in the run position but don't crank the engine. But I do not get a reading from any of the other three. I am grounding to a solid ground (alternator housing). Do I have to have someone cranking the engine in order to get a reading from the other. It is supposedly a closed connection, so I would imagine it should be reading even without cranking. It is the wire that I had to replace the insulation on with electrical tape. The wire looked clean and not corroded.
I am having a heck of a time figuring out the schematics that I have and where the red wire originates. I have a good view of the relay, so I know the red wire is the other wire that should be hot, but it is not an 'always hot' wire, according to the schematics.
Thanks Thomas and thanks to Anthony for sending me some easier to read schematics of the relays. Take Care, Sharon
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As I stated the other two; one is ground for the primary circuit, so 0 volts is expected the other is the secondary circuit which is the fuel pump circuit ( from relay to pump ) so again 0 volts.
The other "hot" terminal is "hot" when the key is in the run position.

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Checked each connection to the relay. Yellow wire coming from the starter relay is the "always hot" wire. That reads fine on the multimeter when the ignition is turned to the on position. Red wire is the other incoming wire and that reads fine when the ignition is cranked. Went back to the inertia switch one last time. Had someone crank the engine and I checked that, nothing, dead. So, I headed back to the brand new relay that I bought. Put the multimeter probe into the socket for the outgoing wire to the inertia switch. Had someone crank the engine, with me grounding to the case of the alternator again, dead. No reading. Tried several times, moved the probe around so I was getting a good contact. Still dead.
I am taking the relay back to AutoZone. I will let you all know if that was it. But I gotta tell you, if it is, I am going to one ticked off lady.
Take Care, Sharon
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Nope, put in another fuel pump relay, same thing. Juice coming in on both sides (one when ignition is on and one when engine is cranked). Absolutely a zilch reading going out. Me thinks that something is really squirrely. I kind of hate to hot wire from the battery directly to the pump, because it may be a grounding problem. And if I have a bad ground, I may blow a perfectly good pump. And a code reader won't help me because, as far as I know, the engine light has never gone on during this whole process, so there would be no codes to read?? I think.
I am not sure what I should do at this point. Maybe change out the contacts to the fuel relay to just regular clips and see if that helps. There is a tan goop in the contact housing that holds the relays. Can someone tell me what that is? It does not feel like dilectic grease to me, it feels sticky. Is it necessary?
Thanks and take care, Sharon
Take Care, Sharon
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This is how the circuit works. Both EEC and Fuel pump relay are hot all the time on the primary circuit. When you turn the key to run the EEC power relay primary circuit is grounded by the ignition switch powering up the ECM and sending power to the secondary side of the Fuel pump relay. The ECM then grounds the primary side of the fuel pump relay for a few seconds to prime the fuel system and then waits for a crank signal. When you turn the key to crank, the processor should see a PIP signal. If it does it grounds the primary side of the fuel pump relay. So what can cause the fuel pup relay to not be grounded? No PIP signal. Bad wire/connection between the fuel pump relay and ECM. Bad relay. This brings us back to square one. Did you check for spark? The ignition system can fail in a number of ways. The ignition system works like this. In side the distributor is the hall switch. It is a device that acts like a light switch, all it does is go open then closed, 6 volts then 0 volts. That signal is sent to the ignition module and the ignition module uses that signal to ground and un-ground the ground side of the ignition coil.That gives you spark. The signal is also sent to the ECM for injector timing and RPM. If the ECM does not see this signal ( called PIP ) it will not ground the fuel pump relay ground and will not pulse the injectors. So if the pass through circuit in the ignition module is open, you will not have fuel delivery yet the ignition system will still be working. The ignition module is suspect in this whole mess.

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Thomas,
The 'always hot' wire on the fuel pump relay and the EEC relays do show juice all the time. So if I check the spark plugs for spark, does that tell me that the Hall effect pickup and the ignition module are ok?
Thanks for your help, take care, Sharon
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As I stated, the ignition system can work and the ECM not see the PIP signal which is why the module is suspect. Checking for spark is a down and dirty way to at least know most of the ignition system works. In other words it rules out a broken timing chain, or a dead coil, or a totally inoperative ignition module or hall switch. With that information you now know to look else where. Like is the ECM getting a PIP signal? If it is, you now know to look else where, like is the ECM making ground on the primary side of the relay? If it is you now know to look else where like is the relay getting power on the secondary side? I don't want to sound rude, and I hope you are not taking it that way. But this is the thought process you need to employ in diagnosing your problem. You need to know what it is and how it works. If you do not, how do you know what is expected and what is not? How to decide what to test and what not to test? So to answer your question, it is a yes and no answer. If you have spark you have a good hall switch, and here is the yes and no, you have a good module in that it is opening and closing the coil ground circuit. The no is cloudy, because the pass-through circuit may be just fine but a poor connection between the module and ECM can prevent the ECM from seeing the signal. This is why I said you need to take a step back and go about this with a little more logic.

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BTW, the "goop" you see is grease installed at the factory to prevent corrosion. It's about the same as white grease.

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While there pick up a code reader if you don't already have one.
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Someone wrote that it may be the ground to the pump. The gas guage is reading fine, which I believe means the ground is ok. I think it may be the connector plugs within the relay socket. At least, that is what I am going to try next. I will try putting normal slip on connectors or go to a junk yard and get a socket. They seem nice and tight to me and in this weather you don't have to worry about rust of any kind. This seems to logically be my next step. If anyone sees something that I may be stupidly missing, I would definitely welcome the advice.
Take Care, Sharon
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The fuel gauge and pump are different circuits with completely different grounds. The ground circuit is easily checked by removing the harness connector from the pump and measuring the resistance from the correct terminal to body.

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I don`t remember, did you try just bypassing the relay and see if the pump will run at all. also when checking, remember the fuel pump relay is only energized about 10 seconds with the key turned on untill the eng starts. so any testing has to take that small window into accout. KB
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Thanks to BeeVee, I found out that there is juice to the pump, but now I have to figure out what is really going on here. I believe what I have done so far is telling me that the connectors inside the socket for the fuel pump relay are bad and here is why:
1) I connected a grounding wire from the fuel tank to the frame. 2) Tried to start the car, no start. 3) I left that ground on and built a jumper wire to hot wire the pump to the battery. Instead of hotwiring it directly to the pump, I decided that I would see if the wires going to the pump were okay. So, I took a small finishing nail and plugged it into the fuel pump relay socket that goes to the fuel pump. I clipped an alligator clip attached to a jumper wire to it and touched the alligator clip at the other end of the jumper wire to the battery (a little different than BeeVee suggested, but accomplishing the same circuit). In any event, the pump came on and ran. I didn't want to run it that way too long, but I did try it several times to make sure it kicked on each time, and it did. 4) If you remember, I already checked the lines going INTO that fuel pump relay and they are showing that they have juice going to them.
It just seems logical to me that if you have the incoming wires testing out fine, and a hotwired outgoing wire testing out fine, that it must be the fuel pump relay socket connectors. I am a little concerned about putting regular clip on connectors to it because I will have some bare connectors that could arc to each other.
Do any of you agree that I should change out those socket connectors next? If so, should I go to a junk yard to get a regular casing connector, or can I use bare metal slip on connectors? Or do you think that there is a possibility that I got TWO bad relays from AutoZone? Seems remote to me. Thanks for any help you can give me. Take Care, Sharon
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To make sure the ECM is grounding the primary side of the pump relay, take the relay out of it's socket. Find the terminal for the ground side of the primary circuit. Put the test lead to it and one to ground, then crank the engine. It seems by what you have been saying you should know what to look for. To double check the secondary terminals make a jumper wire and jump the secondary terminals the pump should run ( key should be in the run position ). If both of these provide a positive result replace the relay. Sounds like you are in the correct area, you just need to put it all together.

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I know this is going to sound like a stupid question Thomas, but which is the primary circuit? Is it the circuit that goes from the always on connection to the fuel pump? Or is it the one that is only on if I crank the engine over? Thanks for answering. I am learning a great deal as I go through this whole process.
Thanks and take care, Sharon
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The primary circuit of a relay is always the circuit that makes the electro magnet, I.E. the coil side of the relay. It just happens on this relay it is the terminal that is always hot. Reread the post 11/9/03 @ 8:30 am. That goes into much more detail.

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Thomas, Sorry, some other crisis things in my life took precedence over the last couple of days, but I still do need your help, PLEASE. My fuel pump relay configuration is:
Fuse Link ! ! yellow - allow hot ! !---------------------------------------! ! ! ! ! / !-----! ! ! / ! ! ! ______!_________________!____!_! ! ! ! orange tan/lt grn red
I put a jumper wire from the yellow to the orange and jumped that to the battery connection (I had removed the positive terminal for safety. Fuel pump kicked on. Then I jumped from the tan/lt grn to the red and attached a jumper from there to the positive battery terminal. Got a clicking noise, and I am not sure from where (can't be in two places at once); but it sounded like the general area of the relays. Oddly enough, sometimes it would happen, sometimes not, even though the pump was going on. Seemed to correlate to the amount of time that I was touching the positive terminal. Lastly, I put a jumper wire from yellow to orange and another one from tan/lt grn to red. Then I put a jumper wire across both, so that they were both getting power. Fuel pump worked, same clicking noise, sometimes, sometimes not.
Can you help me with the next step? And can you answer another question I have? I am assuming that each time I force the fuel pump, gas is going 'somewhere'. Am I flooding an area that will cause me problems if the car ever starts again? Take Care, Sharon
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Please don't conect +12 volts directly to the tan/lt grn wire. Doing that may blow out the computer that wire is what turns the relay on and off. The computer (ECA) switches the tan/lt grn wire to ground to turn on the relay that turns on the fuel pump. Stan

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You may have just answered one of my questions. Then the tan/lt grn wire is the ground wire for the primary circuit??? Take Care, Sharon
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That is how the computer turns the fuel pump on and off. When the computer wants the fuel pump to run it grounds the tan/lt grn wire. That is how the fuel pump is turned on and off .
Hook a volt meter to the tan/lt grn wire with the relay installed and turn the key to run not start . You should read near 0 volts for about 5 seconds then jump up to about 12 volts.
If the tan/lt grn wire always has 12 volts with the key set to run then the computer is not turning on the fuel pump. Stan

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