87 FC no start
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87 FC no start
So I am in the process of getting another 7 but mine has to take me doctor's appointments. Now will not start for anything whereas before it only did the stalling thing between 3800RPM-4500RPM like other FC's. I noticed that whenever the engine was off but the key was is the on position, anytime I touched the wiring for the Throttle position sensor it would cause the relay packs to open & close circuits. Whenever I unplugged the TPS it stopped firing the relays near the EGR relay on/off really fast.
Here is a video that I just uploaded. (It's not edited)
http://www.youtube.com/watch?v=e3pz-Z3DK6Y
Well the good news is that I think I am getting a rental car from my insurance, but I still miss my 7 and want to get it running. Like I said I have never had to deal with this before, I've flooded it but never this.
Here is a video that I just uploaded. (It's not edited)
http://www.youtube.com/watch?v=e3pz-Z3DK6Y
Well the good news is that I think I am getting a rental car from my insurance, but I still miss my 7 and want to get it running. Like I said I have never had to deal with this before, I've flooded it but never this.
Last edited by drchronic; 07-01-11 at 02:14 PM. Reason: Updates
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I found this that seemed kinda relevant "My first thought is that damned safety "feature" that will allow the pump to run while cranking, but will not keep it running unless it senses that you have spark on the trailing ignition system. I suppose an easy way to check this is to see if the float bowls are empty after it stalls." @ https://www.rx7club.com/showthread.p...ighlight=start
I'm not to RX7 savvy so IDK what applies to me.
I'm not to RX7 savvy so IDK what applies to me.
#3
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Believe your link is for carbed engines so this does not apply to you. If you want to make sure the fuel pump does not cut off then jumper the two wire plug that resides near the passenger strut housing/fender that is covered in a black rubber boot and the plug itself is yellow in color. The plug is part of the Emission harness and may be out of sight until you fish for it.
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Believe your link is for carbed engines so this does not apply to you. If you want to make sure the fuel pump does not cut off then jumper the two wire plug that resides near the passenger strut housing/fender that is coverd in a black rubber boot and the plug itself is yellow in color. The plug is part of the Emission harness and may be out of sight until you fish for it.
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Nothing I search is quite my problem, so far I've tried:
Pulling the ECU and checking for any fried components
Disconnecting the TPS, emissions relays, MAF sensor (I think that's what it was)
and a few other things I can't think of at the moment.
I'd say the biggest issue is that I have no tools (stolen) to remove things that are in my way. I wanted to try the recommendation with the fuel pump but I can't find the connector.
If you start it with wide open throttle then usually it will start and rev above 5K rpm's and if you can keep it that high it'll run for 15-20sec.
Also I found this article on replacing an S4 ECU with the Apexi PowerFC model and it mentions this "The fuel-pump relay is not controlled by the ECU for unknown reason. I recommend to install a new relay and replace the old fuel-pump wiring with new solid one. In this case, you can remove the fuel pump resistor mounted on the right side of your car near the right head-light."
The FR headlight is RIGHT where a large dent is from the accident which was a day or two before this started. Could the fuel pump resistor mentioned have been damaged and the whole cause of this? My car has never once done this before the accident.
Pulling the ECU and checking for any fried components
Disconnecting the TPS, emissions relays, MAF sensor (I think that's what it was)
and a few other things I can't think of at the moment.
I'd say the biggest issue is that I have no tools (stolen) to remove things that are in my way. I wanted to try the recommendation with the fuel pump but I can't find the connector.
If you start it with wide open throttle then usually it will start and rev above 5K rpm's and if you can keep it that high it'll run for 15-20sec.
Also I found this article on replacing an S4 ECU with the Apexi PowerFC model and it mentions this "The fuel-pump relay is not controlled by the ECU for unknown reason. I recommend to install a new relay and replace the old fuel-pump wiring with new solid one. In this case, you can remove the fuel pump resistor mounted on the right side of your car near the right head-light."
The FR headlight is RIGHT where a large dent is from the accident which was a day or two before this started. Could the fuel pump resistor mentioned have been damaged and the whole cause of this? My car has never once done this before the accident.
#6
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The "fuel pump relay and resistor" is found on S4 turbos and not S4 non turbos. Perhaps the accident loosened an electrical connection. I would suggest taking a voltage reading from the ECU w/key to on at pin 2I which is the Water Thermosensor that is located on the back of the water pump at the top of it and just behind it. Cold engines read 1 to 3 volts and fully warmed it reads .4 volts. This helps to control fuel upon startup and cruising as well.
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The "fuel pump relay and resistor" is found on S4 turbos and not S4 non turbos. Perhaps the accident loosened an electrical connection. I would suggest taking a voltage reading from the ECU w/key to on at pin 2I which is the Water Thermosensor that is located on the back of the water pump at the top of it and just behind it. Cold engines read 1 to 3 volts and fully warmed it reads .4 volts. This helps to control fuel upon startup and cruising as well.
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#8
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The fuel check connector has a Black wire and a Brown wire and it is in the same harness as the one which supplies the wires to the Pressure sensor.
Post #127 in below link.
https://www.rx7club.com/showthread.p...epotato&page=6
Post #127 in below link.
https://www.rx7club.com/showthread.p...epotato&page=6
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The "fuel pump relay and resistor" is found on S4 turbos and not S4 non turbos. Perhaps the accident loosened an electrical connection. I would suggest taking a voltage reading from the ECU w/key to on at pin 2I which is the Water Thermosensor that is located on the back of the water pump at the top of it and just behind it. Cold engines read 1 to 3 volts and fully warmed it reads .4 volts. This helps to control fuel upon startup and cruising as well.
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I tried jumping that connector for the fuel and it was a no go. No change in it's behavior whatsoever and when I checked pin 2-I on the ECU with the motor OFF and the ignition ON it reads .025-.03V. From what you have said I think that is at least 1 of the issues if it's supposed to be 1-3vDC.
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Yep, overnight. In fact it's been sitting for a few days. What does low voltage mean? To be honest I am overwhelmed, this is (or was) my daily driver and it was practically bulletproof reliable before the accident.
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That would make sense because normally if the car didn't start properly the first time then the second time you crank the motor it'd flood. In all the times I've tried to get it running it has never flooded which I though very weird. I'm confused though on exactly which connector you mean, the one connecting directly to the fuel pump? I have checked the ECU's molex connector.
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That would make sense because normally if the car didn't start properly the first time then the second time you crank the motor it'd flood. In all the times I've tried to get it running it has never flooded which I though very weird. I'm confused though on exactly which connector you mean, the one connecting directly to the fuel pump? I have checked the ECU's molex connector.
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be nice to your mom. what push rod moving back and forth are you talking about?
go to autozone, rent a fuel pressure tester... go from there. It's obvious it gets spark. the blue smoke is fuel.
go to autozone, rent a fuel pressure tester... go from there. It's obvious it gets spark. the blue smoke is fuel.
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I'm wondering if the fuel pump pulled something from the gas tank and clogged. The tank was removed by the previous owner (IDK why) and when it was put back they jacked the breather valve and now I have to trickle fuel in.
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HOORAY IT"S ALIVE. I pulled off a very poorly made wire extension off of the Thermosensor and Viola it reads 2-3v on pin 2I but it was jumping up to 10v occasionally and the car is running SUPER rich. I let it run for a few minutes (as long as I could stand the fumes) and shut it off. I have a rental for now but I need to get it sorted. All I changed was the throttle screw, would that cause this or is there still a gremlin under the hood?
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Yeah something is still very wrong because it ran fine for a while and is now having the exact same problem. The other day it stalled a block from my house and I was moving so I just roll started it to get it home. I am out of idea's other than rewiring that whole section of the harness. The insulation is disintegrating and my relays are tripping again when you move the wires.
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