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> 1972 1.7 not starting
ctkellett
post Aug 27 2015, 10:22 AM
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I bought a stock running project car with a bad tail shift transmission. I pulled the motor and replaced the transmission with a freshly rebuilt side shift unit from 914 LTD.

After the reinstall I am not able to get the car running again.

Things that I have double checked

-Fuel Pump runs and primes when the ignition gets switched on at the key
-confirmed spark at the coil and at the plug with motor cranks
-can hear the injectors pump once while the fuel pump is priming and when you step on the gas pedal once.
-confirm that the timing is set correctly, that the points are gapped correctly.
- the car will run briefly on starter fluid.

Any thoughts? Maybe and ECU issue? Where do the injectors get the signal to fire?

Thanks!

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914itis
post Aug 27 2015, 10:30 AM
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Injector grounds ?

Back of the engine towards the trunk . Follow the ECU harness.
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Tom
post Aug 27 2015, 12:23 PM
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Double check that you don't have the fuel lines reversed. Seen this too many times.
Tom
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ctkellett
post Aug 27 2015, 01:03 PM
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QUOTE(Tom @ Aug 27 2015, 02:23 PM) *

Double check that you don't have the fuel lines reversed. Seen this too many times.
Tom



Thanks, I will double check this one. I figured that grounds on the injectors were good if they fired when I stepped on the gas after the fuel pump primed but I will triple check that just incase.
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Bob L.
post Aug 27 2015, 02:01 PM
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Ground strap at the back of transmission to body under trunk?
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Tom
post Aug 27 2015, 08:52 PM
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ck,
I was referring to the fuel lines that connect to the engine from the tank. The supply should be hooked to the passenger side fuel injection rail, then run over to the driver's side and then to the fuel pressure regulator, and finally to the other line on the passenger side going to the tank that should be the return. To make sure you have the supply line properly identified, loosen and remove the line you now have going to the passenger side fuel rail and put a glass/plastic bottle under it. Turn the key on for the 1.5 second prime and see if you have fuel coming out of the line from the tank. If so, then you have them hooked up right. If no gas, reverse them and see what happens.
Tom
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ctkellett
post Aug 29 2015, 08:00 AM
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Thanks again for the suggestion, I double checked the grounds on the trans- body and the injector grounds below the intake manifold and both are on and working.

I checked the pump, the suction feed ( S ) Y's at the head of the pump and feeds the send side of the fuel injection fuel loop. The pump will send fuel via the feed side of the fuel line when I turn the key but if I crank the car the pump seems to stop feeding fuel down the line. I have two new fuel relays on the relay board and I took all of the black junk off the bottom of the board and checked all of the the pin feeds for continuity. Power is getting to all of the Pin 13's for the relays.

I have started to dig into the D Jet trouble shooting postings but I have not yet run across this issue yet.


Thanks for any help you can offer.

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Dave_Darling
post Aug 29 2015, 09:53 AM
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I think you've found your problem. The Y should be in the return part of the circuit, not the suction side.

The lines should go:
- Fuel tank to larger center tunnel line
- Larger center tunnel line to fuel filter
- Fuel filter to 'S' port on fuel pump
- 'D' port on fuel pump to passenger's side fuel rail
- Passenger's side fuel rail to driver's side fuel rail
- Driver's side fuel rail to fuel pressure regulator
- Fuel pressure regulator to Y
- Y to 'R' port on fuel pump
- Y to smaller line through center tunnel
- Smaller line through tunnel to tank

It sounds like you have some hoses swapped.

--DD
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ctkellett
post Sep 2 2015, 02:53 PM
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QUOTE(Dave_Darling @ Aug 29 2015, 11:53 AM) *

I think you've found your problem. The Y should be in the return part of the circuit, not the suction side.

The lines should go:
- Fuel tank to larger center tunnel line
- Larger center tunnel line to fuel filter
- Fuel filter to 'S' port on fuel pump
- 'D' port on fuel pump to passenger's side fuel rail
- Passenger's side fuel rail to driver's side fuel rail
- Driver's side fuel rail to fuel pressure regulator
- Fuel pressure regulator to Y
- Y to 'R' port on fuel pump
- Y to smaller line through center tunnel
- Smaller line through tunnel to tank

It sounds like you have some hoses swapped.

--DD


Darn, turns out that they were correct and I made a mistake when I looked at pump photo instead of looking at my pump in the car. So, all the hoses were correct. I am still not seeing any pump pressure after the first burst after the key has been turned to the on position. Where does the pump receive the command to run from once the motor starts to crank?

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Dave_Darling
post Sep 2 2015, 05:39 PM
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From the FI ECU. It grounds one of the pins in the four-pin harness, which triggers the fuel pump relay, sending power to the pump.

--DD
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ctkellett
post Sep 7 2015, 02:08 PM
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QUOTE(Dave_Darling @ Sep 2 2015, 07:39 PM) *

From the FI ECU. It grounds one of the pins in the four-pin harness, which triggers the fuel pump relay, sending power to the pump.

--DD



Thanks Dave, guess I will see if I can track down a replacement ECU.
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