Finished Z31 ECU swap... but now problem...
03-09-2007, 02:21 PM
#26
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Originally Posted by xtreme 2
so I just double-checked the wiring harness, and everything is connected how it should be except the #20 wire. It shows on the diagram that for the Z31 ECU it goes to the Fuel Pump Relay, but the 280zx wiring harness does not have a wire there. What am I supposed to do there?
03-09-2007, 10:35 PM
#29
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how? why would a ground only affect the car when it's in gear? in neutral the car fires up and idles/revvs all day long...
what ground would affect this? please give reasoning behing your thoughts...
what ground would affect this? please give reasoning behing your thoughts...
03-10-2007, 01:06 PM
#30
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ok, so after much trial and error, installing an adjustable FPR thinking that the Fuel Pressure was too high, adding a fuel stabilizer, and then cranking with the relay off, we went to start and discovered that there is no fuel coming into the system. I pulled off the hoses on each side of the FPR and found both are dry, so there is no fuel entering or leaving the system. I double-checked and the wires for the fuel pump and the air regulator are properly switched, but that isn't fixing the problem.
We have resulted that the problem lies with pin 20, despite the fact that everyone says it isn't necessary. We looked and figure that the best place to hardwire the pin to would be Fuel Pump Relay 1 on the passenger side of the car. However, there are 5 wires going into the relay, and I am unsure which one to tap into. Any help?
We have resulted that the problem lies with pin 20, despite the fact that everyone says it isn't necessary. We looked and figure that the best place to hardwire the pin to would be Fuel Pump Relay 1 on the passenger side of the car. However, there are 5 wires going into the relay, and I am unsure which one to tap into. Any help?
03-10-2007, 08:19 PM
#32
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Originally Posted by y2daniel1981
Also today the wastegate popped when we tried to start it after putting on the FPR.
I'm about just ditch this engine and do a v8 swap with everything that's been going wrong
I'm about just ditch this engine and do a v8 swap with everything that's been going wrong
Take a deep breath, collect your thoughts and fix what was not broken until you decided to "Upgrade" it
Rod.
03-10-2007, 09:18 PM
#33
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Originally Posted by RodMoyes
Things are only going "Wrong" because you dicked with it...
Take a deep breath, collect your thoughts and fix what was not broken until you decided to "Upgrade" it
Rod.
Take a deep breath, collect your thoughts and fix what was not broken until you decided to "Upgrade" it
Rod.
03-10-2007, 09:18 PM
#34
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umm not sure how that reply is helping the situation, but okay...
forums are for helping people. When we couldn't figure out the problem ourselves, we posted for help. People replied with suggestions, we tried them, and they made no difference. It's not a ground, because the engine fires up fine, just isn't getting fuel after a bit. Just need suggestions why, and then we will fix it and be fine...
forums are for helping people. When we couldn't figure out the problem ourselves, we posted for help. People replied with suggestions, we tried them, and they made no difference. It's not a ground, because the engine fires up fine, just isn't getting fuel after a bit. Just need suggestions why, and then we will fix it and be fine...
03-10-2007, 10:59 PM
#35
Originally Posted by RodMoyes
Things are only going "Wrong" because you dicked with it...
03-10-2007, 11:17 PM
#37
You might have toasted something. The purpose for PIN 108 is to allow the ecu to open the ground to the fuel pump relay when the fuel pump should be working (thus turning on the fuel pump). PIN 20 looks to be a power wire to the fuel pump relay.... you tied a + wire to a - wire.....
03-10-2007, 11:42 PM
#38
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Hmm that wouldn't be good. I am looking at the write-up from HybridZ and comparing it you your Excel Spreadsheet, and the only difference I am seeing is that on your sheet it says to just switch the wire from pin 16 with the wire from pin 108 so that the Fuel Pump and Air Regulator are operated differently. On the HybridZ write-up, it tells to switch the wire from pin 108 to pin 16, but to cut the black wire going into the Fuel Pump Relay 1 and to run it to pin 108.
Does this just bypass the relay doing it their way or what?
Does this just bypass the relay doing it their way or what?
03-10-2007, 11:56 PM
#39
Originally Posted by xtreme 2
On the HybridZ write-up, it tells to switch the wire from pin 108 to pin 16, but to cut the black wire going into the Fuel Pump Relay 1 and to run it to pin 108.
Originally Posted by xtreme 2
Does this just bypass the relay doing it their way or what?
03-11-2007, 12:20 AM
#42
Originally Posted by xtreme 2
and I go from the relay to the ECU, not the wire to the ECU?
Originally Posted by NismoPick
You cut the black wire just after the fuel pump relay and run it (the wire still connected to the relay) to pin 108 on the ECU.
In other words...
You leave the black fpr wire going into the body wiring harness dangling unconnected. If you connect PIN 108 to that wire, you ground a ground and the fuel pump no workie.
This should be pretty simple.
03-13-2007, 08:32 PM
#44
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ok, that is done. Now which wire do I ground to the chassis for the fuel pump? When I removed the cover in the back of the car, I see the black and yellow wires coming up next to the fuel lines, but that black wire already looks grounded.
Just wanting to do this right without making major mistakes...
Just wanting to do this right without making major mistakes...
03-22-2007, 12:49 PM
#50
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still couldn't get the fuel pump to work using that method... I dunno if there is something wrong with the ECU or what.
Just to see what the problem was, I hardwired the Fuel Pump today with a toggle switch and when turned on and pressurized the car starts, but now does not want to idle. As long as my foot stays on the gas, I am able to drive it around no problems. However, it cannot be driven this way, as is apparent.
Also, the last time I started it, it continually backfired until I shut it off. Acted as though it was still starving for fuel... going to check timing tomorrow when I can get a friend to help me, any other ideas?
Just to see what the problem was, I hardwired the Fuel Pump today with a toggle switch and when turned on and pressurized the car starts, but now does not want to idle. As long as my foot stays on the gas, I am able to drive it around no problems. However, it cannot be driven this way, as is apparent.
Also, the last time I started it, it continually backfired until I shut it off. Acted as though it was still starving for fuel... going to check timing tomorrow when I can get a friend to help me, any other ideas?
