1972 1.7 not starting |
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1972 1.7 not starting |
ctkellett |
Aug 27 2015, 10:22 AM
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#1
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Newbie Group: Members Posts: 12 Joined: 18-February 15 From: PA Member No.: 18,450 Region Association: None |
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! |
914itis |
Aug 27 2015, 10:30 AM
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#2
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Advanced Member Group: Members Posts: 2,892 Joined: 9-October 10 From: New York City Member No.: 12,256 Region Association: North East States |
Injector grounds ?
Back of the engine towards the trunk . Follow the ECU harness. |
Tom |
Aug 27 2015, 12:23 PM
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#3
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Advanced Member Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None |
Double check that you don't have the fuel lines reversed. Seen this too many times.
Tom |
ctkellett |
Aug 27 2015, 01:03 PM
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#4
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Newbie Group: Members Posts: 12 Joined: 18-February 15 From: PA Member No.: 18,450 Region Association: None |
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. |
Bob L. |
Aug 27 2015, 02:01 PM
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#5
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Senior Member Group: Members Posts: 847 Joined: 7-August 11 From: Austin TX Member No.: 13,411 Region Association: Southwest Region |
Ground strap at the back of transmission to body under trunk?
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Tom |
Aug 27 2015, 08:52 PM
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#6
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Advanced Member Group: Members Posts: 2,139 Joined: 21-August 05 From: Port Orchard, WA 98367 Member No.: 4,626 Region Association: None |
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 |
ctkellett |
Aug 29 2015, 08:00 AM
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#7
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Newbie Group: Members Posts: 12 Joined: 18-February 15 From: PA Member No.: 18,450 Region Association: None |
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. |
Dave_Darling |
Aug 29 2015, 09:53 AM
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#8
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914 Idiot Group: Members Posts: 14,974 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
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 |
ctkellett |
Sep 2 2015, 02:53 PM
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#9
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Newbie Group: Members Posts: 12 Joined: 18-February 15 From: PA Member No.: 18,450 Region Association: None |
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? |
Dave_Darling |
Sep 2 2015, 05:39 PM
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#10
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914 Idiot Group: Members Posts: 14,974 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
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 |
ctkellett |
Sep 7 2015, 02:08 PM
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#11
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Newbie Group: Members Posts: 12 Joined: 18-February 15 From: PA Member No.: 18,450 Region Association: None |
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