fuel pump problem (important pls look)
02-24-03, 04:14 PM
#26
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OK!
the pins on the circuit opening relay checked ok for resistance.
the plug, however, has bad voltage for the Fp pin...0 throughout the board, except in the start position. i tried holding the flap on the afm, jumpering the connector....nothing.
the pins on the circuit opening relay checked ok for resistance.
the plug, however, has bad voltage for the Fp pin...0 throughout the board, except in the start position. i tried holding the flap on the afm, jumpering the connector....nothing.
02-24-03, 04:41 PM
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ok so i'm thinking that the wire from the AFM to the circuit opening relay has been shorted or something. is this a straight wire, from the relay to the AFM? the fsm makes it seem so.
so, if it is a bad wire, can i just replace this.
thanks for all your help hailers...i think ive tracked it down to this. let me know if this sounds right.
so, if it is a bad wire, can i just replace this.
thanks for all your help hailers...i think ive tracked it down to this. let me know if this sounds right.
02-24-03, 04:53 PM
#28
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I don't think its a straight shot. I think there is a connection in between. Unfortunatly I am not near my manual.
The wire from the afm to the relay is supposed to put a ground on the relay, not voltage. So if you were on that wire (black) at the relay, with a meter on ohms, and then pushed on the afm'S flapper door, you should get a reading. Something under 1 ohm for sure.
If that wire was shorted to ground, the relay would be pulled in any time the key was on.
The wire from the afm to the relay is supposed to put a ground on the relay, not voltage. So if you were on that wire (black) at the relay, with a meter on ohms, and then pushed on the afm'S flapper door, you should get a reading. Something under 1 ohm for sure.
If that wire was shorted to ground, the relay would be pulled in any time the key was on.
02-24-03, 05:02 PM
#29
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as per FSM, with the flap open, i should get 12v at the Fp pin. no voltage there. i get 0, except in the start position.
please take a look at your fsm when you get the chance...i cant seem to find anyone else that knows the schematics to this thing.
please take a look at your fsm when you get the chance...i cant seem to find anyone else that knows the schematics to this thing.
Last edited by kep0ne; 02-24-03 at 05:06 PM.
02-24-03, 06:42 PM
#30
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Oh. Ok. I looked online at http://www.iluvmyrx7.com page 4A-74
Ok. Try this. Leave the connector on the relay. Turn the key to ON. Now get a piece of wire bare at each end. Put one end to a ground. Now put the other end into the back of the wire called Fc in the picture. I'm looking at the 88 manual and it says that wire should be Black/Red. When you do that the relay should pull in. It probably will.
If it did, take that bare wire and set it to the side. Now pull the plug off the relay. Now put your meters positive lead on the black/red wire and the negative wire on a good ground. Your meter should show less than one ohm IF the flapper door is opened OR a jumper is put in the fuel pump check connector near the front strut tower. IF you have no resistance, then the wire is indeed open between the relay and the afm/check connector.
Or here's another thought. Maybe the ground for the afm/check connector is broken. To prove that, go to the brown/red wire at the check connector and jumper it directly to ground. Then turn the key on and see if the relay pulls in.
I really, really, really, would do what I said in the begining of this answer. Pull the plug off the relay. Put a meter on ohms and see if the black/red wire has a ground on it when the flapper door is opened OR when a jumper is put on the fuel pump check connector. IF a ground of approx one ohm or less is not seen on the meter when the flapper is opened, then the wire is busted b/t the relay and afm (or the ground wire at the afm/check connector is busted.
When a jumper is inserted b/t the two sockets on the fuel pump check connector, you are doing the same thing as what the afm does when the flapper door opens. The afm and the check connector share the same ground wire and the same B/R wire. See page 50-25 of the 88 manual(wiring section) called EGI AND EMISSION CONTROL SYSTEM.(bottom of that page).
Ok. Try this. Leave the connector on the relay. Turn the key to ON. Now get a piece of wire bare at each end. Put one end to a ground. Now put the other end into the back of the wire called Fc in the picture. I'm looking at the 88 manual and it says that wire should be Black/Red. When you do that the relay should pull in. It probably will.
If it did, take that bare wire and set it to the side. Now pull the plug off the relay. Now put your meters positive lead on the black/red wire and the negative wire on a good ground. Your meter should show less than one ohm IF the flapper door is opened OR a jumper is put in the fuel pump check connector near the front strut tower. IF you have no resistance, then the wire is indeed open between the relay and the afm/check connector.
Or here's another thought. Maybe the ground for the afm/check connector is broken. To prove that, go to the brown/red wire at the check connector and jumper it directly to ground. Then turn the key on and see if the relay pulls in.
I really, really, really, would do what I said in the begining of this answer. Pull the plug off the relay. Put a meter on ohms and see if the black/red wire has a ground on it when the flapper door is opened OR when a jumper is put on the fuel pump check connector. IF a ground of approx one ohm or less is not seen on the meter when the flapper is opened, then the wire is busted b/t the relay and afm (or the ground wire at the afm/check connector is busted.
When a jumper is inserted b/t the two sockets on the fuel pump check connector, you are doing the same thing as what the afm does when the flapper door opens. The afm and the check connector share the same ground wire and the same B/R wire. See page 50-25 of the 88 manual(wiring section) called EGI AND EMISSION CONTROL SYSTEM.(bottom of that page).
02-24-03, 06:52 PM
#31
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i will definitely try that as soon as i can...i have class in about an hour.
im thinking its a bad ground also...since i have to go to class, im going to have to try this in the morning.
can you verify via the fsm if the wire to the AFM from the circuit opening relay is just one wire, straight shot?
again, ill test it as per your instructions, and should have a post with the results in the morning.
again, thanks a lot hailers...you've helped me narrow this thing down quite a bit.
im thinking its a bad ground also...since i have to go to class, im going to have to try this in the morning.
can you verify via the fsm if the wire to the AFM from the circuit opening relay is just one wire, straight shot?
again, ill test it as per your instructions, and should have a post with the results in the morning.
again, thanks a lot hailers...you've helped me narrow this thing down quite a bit.
02-24-03, 06:52 PM
#32
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Your not getting 12v on the Fp in any other position except start...because the relay is not pulling in.
The relay needs 12v on the coil for it to pull in and also a ground (from the afm/check connector).
Do you have 12v on the B/W wire when the key is to on???
The relay needs 12v on the coil for it to pull in and also a ground (from the afm/check connector).
Do you have 12v on the B/W wire when the key is to on???
02-24-03, 07:12 PM
#33
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I just looked. No its not a straight shot to the afm from the relay. There is a 14 pin connector near the blower motor that seperates the two. They call that connector FEM-02, and page 50-33 of the wiring diagrams shows a vague description of where it is.
If you had a long piece of wire you could put one end in the connector of the afm (black/red wire) and run it to one of your meters leads, then the other meter lead to the connector of the relay (black/red wire) and see if you have continuity. If so, then the wire is ok. Have both connectors off when you do that.
There seems to be a difference in wire colors b/t the 87 schematic I posted and the 88 manual I'm looking at online. It would be helpful if you could confirm that you have a black/red wire in the relay plug on your car. Otherwise most of the above is gibberish.
If you had a long piece of wire you could put one end in the connector of the afm (black/red wire) and run it to one of your meters leads, then the other meter lead to the connector of the relay (black/red wire) and see if you have continuity. If so, then the wire is ok. Have both connectors off when you do that.
There seems to be a difference in wire colors b/t the 87 schematic I posted and the 88 manual I'm looking at online. It would be helpful if you could confirm that you have a black/red wire in the relay plug on your car. Otherwise most of the above is gibberish.
02-24-03, 07:34 PM
#34
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grounding the Fc pin closes the relay, and it clicks.
also i get no resistance when i use my ohmmeter on that pin, either with the jumper connector, or the AFM flap pushed open. nothing there.
could i just run a ground to the pin E1 on the AFM connector, and a wire from Fc on AFM, to Fc on circuit opening relay? this would bypass the harness by the blower motor.
i could also run a ground from the Fc pin on the circuit opening relay, but id rather run it from the AFM connector for safety reasons.
and yes your wire colors correspond with mine.
im 100% convinced that the wire has gone bad somewhere.
also i get no resistance when i use my ohmmeter on that pin, either with the jumper connector, or the AFM flap pushed open. nothing there.
could i just run a ground to the pin E1 on the AFM connector, and a wire from Fc on AFM, to Fc on circuit opening relay? this would bypass the harness by the blower motor.
i could also run a ground from the Fc pin on the circuit opening relay, but id rather run it from the AFM connector for safety reasons.
and yes your wire colors correspond with mine.
im 100% convinced that the wire has gone bad somewhere.
02-24-03, 08:07 PM
#35
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It would be useful if one went to the afm, pulled the connector off and got on the black wire with a meter and see if it is going to a good ground. That black wire uses the same ground as the fuel pump check connector. According to the fsm that ground is the same one used by the ECU(pins 3G and 3A) and the shield for the o2 sensor.
That ground is located under the dynamic chamber.
Just a little more info.
You could do that rewire....but I wouldn't. You need to find out why there is no continuity b/t the afm (Fc) to the relay (Fc). That seems to be the open wire, but could be that the wire that goes from E1 on the afm is the one that is open and not going to its ground.
That ground is located under the dynamic chamber.
Just a little more info.
You could do that rewire....but I wouldn't. You need to find out why there is no continuity b/t the afm (Fc) to the relay (Fc). That seems to be the open wire, but could be that the wire that goes from E1 on the afm is the one that is open and not going to its ground.
Last edited by HAILERS; 02-24-03 at 08:15 PM.
02-24-03, 10:50 PM
#36
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but either wire, whether it be the Fp wire from AFM to COR, or the E1 wire from AFM to ground...whichever one is open, needs to be replaced...i think we can both agree on that. ill just replace whichever one tests bad tomorrow.
02-25-03, 11:49 AM
#37
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I know that this is getting to be a long drawn out thread, but I was curious.........when you jumper a ground to the black/red wire at the relay, pulling it in, does the car run?? Assuming everything else is also connected up like the afm????
03-14-03, 09:49 PM
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sorry about hijacking the thread on ya but I have a question....Hailers--I am in the process of pulling my injectors to have them cleaned, and I took off the intake tubing today. (86 GXL all stock) When I went to remove the connector from the afm, all the pins were there, but it looked like a mess...the wires looked like something wasnt connected and one of the connectors either was broken or broke when I removed it. I didnt yank it around or anything either...just unscrewed the screws and pulled it out
my car wont even start....tried the unflooding tricks but not working and thats why I was pulling the injectors...could that bad connection cause the car to not start at all?? I put some oil in the plug holes and tried to start it, and it sputters and dies right away and leaves me in the smoke....
my car wont even start....tried the unflooding tricks but not working and thats why I was pulling the injectors...could that bad connection cause the car to not start at all?? I put some oil in the plug holes and tried to start it, and it sputters and dies right away and leaves me in the smoke....
03-14-03, 10:02 PM
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sorry about hijacking the thread on ya but I have a question....Hailers--I am in the process of pulling my injectors to have them cleaned, and I took off the intake tubing today. (86 GXL all stock) When I went to remove the connector from the afm, all the pins were there, but it looked like a mess...the wires looked like something wasnt connected and one of the connectors either was broken or broke when I removed it. I didnt yank it around or anything either...just unscrewed the screws and pulled it out
my car wont even start....tried the unflooding tricks but not working and thats why I was pulling the injectors...could that bad connection cause the car to not start at all?? I put some oil in the plug holes and tried to start it, and it sputters and dies right away and leaves me in the smoke....
my car wont even start....tried the unflooding tricks but not working and thats why I was pulling the injectors...could that bad connection cause the car to not start at all?? I put some oil in the plug holes and tried to start it, and it sputters and dies right away and leaves me in the smoke....
03-15-03, 12:54 AM
#41
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Ooooops. Sorry 'bout that. The afm plug pulls straight off. No unscrewing involved at all. You made a mistake. Just say oooops, and buy another afm. I don't know what else to say. I can't see what you have, but it's probably terminaly broken.
Key words: no unsrewing involved at all.
You unscrewed the JACK on the afm. Not desireable. The plug is the part of the harness. It just pulls straight off the JACK. Like I said, the jack is screwed to the afm. More or less premantly. There is usually a spring clip that has to be moved aside for the plug to be removed from the JACK.
Spend 25 to 50 for another afm at the junk yard. Make sure it came off a 86-88 model. Others won't work.
Key words: no unsrewing involved at all.
You unscrewed the JACK on the afm. Not desireable. The plug is the part of the harness. It just pulls straight off the JACK. Like I said, the jack is screwed to the afm. More or less premantly. There is usually a spring clip that has to be moved aside for the plug to be removed from the JACK.
Spend 25 to 50 for another afm at the junk yard. Make sure it came off a 86-88 model. Others won't work.
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