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95 3000GT vr4
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Discussion Starter #1
last week i brought the car in for paint,the day i tried to pull it into the booth i was getting to fuel i wired the fuel pump strait to the battery and it started just fine after the car was painted i hauled it home started working on putting parts on the car, i pulled the car outside to build a new workbench it sat outside for the night the next day it was hard to start, i pulled it inside the the next time i tried to start it it wont start at all i checked fuel and spark i was getting both it sounds like it wants to start i have no clue where to go from here.
 

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93 NA ATX 3000gt DOHC
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Have you been able to identify model year yet?
 

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93 NA ATX 3000gt DOHC
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Since your problem started with pump not running and got worse from there, it would seem logical to start troubleshooting fuel system. Not being there to troubleshoot requires some info to help analyze.
1. Are you using pump test connector for hot wire to pump?
2. How are you checking fuel pressure and flow when you say checked fuel?
3. Do you hear MFI relay (console right side of radio) click when you first turn key to on?
4. How many miles or time on timing belt since last changed?
5. Do you have multi-meter and know how to use it?
 

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95 3000GT vr4
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Discussion Starter #5
1. hot wire to pump i couldn't find the test connector
2. I checked fuel pressure by taking the main line off the injector rail put it in a bottle and was getting quite a bit of flow therefore thinking i have fuel pressure.
3. there is no click from there when i first turn the key on
4. timing belt was changed just before painting i bet not even 3 hours on it
5.yes and yes
 

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93 NA ATX 3000gt DOHC
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1. hot wire to pump i couldn't find the test connector
2. I checked fuel pressure by taking the main line off the injector rail put it in a bottle and was getting quite a bit of flow therefore thinking i have fuel pressure.
3. there is no click from there when i first turn the key on
4. timing belt was changed just before painting i bet not even 3 hours on it
1.Pump test connector is black one of the three near bottom of wiper motor. Blue connector is for engine RPMs, Tan one is for grounding to set couple different items for adjustments and Black one is for applying power straight to fuel pump.
3K  test connectors.jpg

2. That’s OK for flow, but not for pressure as it should be ~ 45 psi which would blow fuel everywhere if shot into a bottle. May have to look at that latter as pressure most likely reduced by open line.

3.
This one is of most concern but puzzling, because if it wasn’t closing when key tuned to on you wouldn’t get spark which you say you have, also it can affect fuel pump operation (won’t get into that right now). It points to bad MFI rely (as HOSS indicates), but before replacing you should check couple of fuses after which you can run voltage checks to verify.

a) First check 20amp #1 dedicated fuse in box under hood behind right head light, might be marked ECI on cover. It should be hot all the time and of course not be blown.
b) Next check 15 amp #12 fuse inside under dash middle row far right.
fuse box.JPG
Depending on what you find with fuses we'll move on with voltage checks at MFI relay itself.

4. Possibly something loosened up in there, but wouldn’t explain lost of fuel pressure in first place.

I would fist concentrate of # 3 and go from there.
 

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93 NA ATX 3000gt DOHC
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I don’t know if you’re pump hot wire is switched or not. But I should’ve told you if you run jumper from battery positive post to pump test connector, ignition switch will not turn pump off, it will run as long as jumper is connector.
 

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95 3000GT vr4
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Discussion Starter #9
Thanks guys for the help
I tested those 2 fuses and there fine
286819

Is this the MFI if so I will grab one tomorrow out of a parts car

i have just been connecting my bumper wire to the pump when I try and start it
 

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93 NA ATX 3000gt DOHC
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Is this the MFI if so I will grab one tomorrow out of a parts car
Yes that is MFI relay, but it's up to you if you want to spend money on a relay before testing to find out if it isn't something else keeping it from working like maybe ECU that controls it. I don't have time right now but this afternoon I can detail a few checks to narrow down. Of course if you have a spare on hand that might be easy.
 

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93 NA ATX 3000gt DOHC
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Since I’m not sure if I should be waiting for reply from you I’ll include the test I mentioned. These are voltage test at ECU pins with connectors still plugged in; couple of test will also tell if MFI relay is working as well. Do these checks and report any not correct.

Pin 12, 25 & 82 Ign ON should be ~12 volts

Pin 81 Ign ON should be 4.5 – 5.5 volts

Pin 8 Ign ON should be ~12 volts
Ign Start position (cranking) should be 0 – 3 volts

Pin 38 Ign OFF should be ~12 volts
Ign ON should be 0 – 3 volts

Pin 80 Ign OFF should be ~ 12 volts
94-97 ECU pins.JPG
 

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93 NA ATX 3000gt DOHC
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Opps, sorry had to edit pins 8 & 38 (senior moment) be sure to look at above post again.
 

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Please disregard my last statement after seeing the wiring diagram for a 93+ their seems to be a direct connection from the crank sensor to the mfi so a 1/2bad sensor could cause the mfi not fire the injectors
 

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95 3000GT vr4
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Discussion Starter #16
Thanks, I’ll try that tonight and see what I get out of that.
 

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Discussion Starter #17
I think the crank angle sensor is good beings as I just replaced it, I will test it though.
 
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