Fuel injection not working, 73 2 liter |
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Fuel injection not working, 73 2 liter |
smveril |
Nov 3 2019, 01:28 PM
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#1
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Mikey Group: Members Posts: 50 Joined: 6-December 04 From: Cincinnati, OH Member No.: 3,232 Region Association: Upper MidWest |
I have a 73 2 liter that I am near the end of the restoration.
We are trying to get the car to run. The engine is rebuilt, it has a Bosley fuel injection harness. We pulled two injectors and we saw no fuel flow. The fuel pump runs and we have fuel pressure. We then removed the ECU and checked the pin outs on the ECU cable per Paul Andres schematic. One thing we found was the start signal from the ignition switch was 10.5 volts. It should be greater than 12 volts (pin 18 and ground). What could cause the low voltage to the ECU? Thanks, Mike . |
Bleyseng |
Nov 4 2019, 04:02 PM
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#2
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Aircooled Baby! Group: Members Posts: 13,034 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
Does it start on starting fluid?
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sixnotfour |
Nov 4 2019, 04:08 PM
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#3
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914 Wizard Group: Members Posts: 10,392 Joined: 12-September 04 From: Life Elevated..planet UT. Member No.: 2,744 Region Association: Rocky Mountains |
fuel lines backwards
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smveril |
Nov 4 2019, 07:53 PM
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#4
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Mikey Group: Members Posts: 50 Joined: 6-December 04 From: Cincinnati, OH Member No.: 3,232 Region Association: Upper MidWest |
It will run on starting fluiid. We did check the fuel lines but it may make sense to measure fuel pressure. But we are getting 10.5 volts to the ECU instead of 12 volts. So the fuel injectors do not enough power to run.
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smveril |
Nov 4 2019, 08:17 PM
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#5
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Mikey Group: Members Posts: 50 Joined: 6-December 04 From: Cincinnati, OH Member No.: 3,232 Region Association: Upper MidWest |
So, I am looking for ideas that restrict the ECU from getting 12 volts power
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jcd914 |
Nov 4 2019, 10:21 PM
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#6
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
One thing we found was the start signal from the ignition switch was 10.5 volts. It should be greater than 12 volts (pin 18 and ground). The power to the ECU from the starter circuit is so the ECU will power up the fuel pump while the engine is being cranked over. The ECU probably does not need the full 12 volts in order to power the fuel pump. Does the fuel pump run while cranking the engine? The starter circuit is notorious for low voltage to the starter. Many people have added relays or the Ford start solnoid to get the starter to engage. I have never heard anyone having an issue with the low voltage to the ECU from this same circuit. The ECU gets battery voltage it uses for operation from a different circuit bia the power supply relay on the engine compartment relay panel. Check fuel pressure. Check the 3 ground wires at the top rear of the engine case bolt. Check for voltage pulses at the injectors, a mood light is the simplest way to check this. Check the connector for injector points in distributor, needs to be tight. Jim |
porschetub |
Nov 4 2019, 11:10 PM
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#7
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Advanced Member Group: Members Posts: 4,695 Joined: 25-July 15 From: New Zealand Member No.: 18,995 Region Association: None |
or bad ignition switch ?????.
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914_teener |
Nov 5 2019, 11:04 AM
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#8
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914 Guru Group: Members Posts: 5,193 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
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smveril |
Nov 5 2019, 05:50 PM
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#9
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Mikey Group: Members Posts: 50 Joined: 6-December 04 From: Cincinnati, OH Member No.: 3,232 Region Association: Upper MidWest |
The fuel pump does run. I replaced the ignition switch about 6 years ago when it failed.
I will check fuel pressure. I did clean all the grounds when I pump the engine back in the car. Thanks for the other suggestions. I will try them. I have another question. The new injection harness had the coil wire labels switched. Could that damage the ECU. Thanks, Mike |
914_teener |
Nov 5 2019, 06:20 PM
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#10
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914 Guru Group: Members Posts: 5,193 Joined: 31-August 08 From: So. Cal Member No.: 9,489 Region Association: Southern California |
The fuel pump does run. I replaced the ignition switch about 6 years ago when it failed. I will check fuel pressure. I did clean all the grounds when I pump the engine back in the car. Thanks for the other suggestions. I will try them. I have another question. The new injection harness had the coil wire labels switched. Could that damage the ECU. Thanks, Mike ? What lead of the FI harness plugs into the coil terms? Post a Pic. |
jack20 |
Nov 8 2019, 12:18 AM
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#11
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Member Group: Members Posts: 404 Joined: 7-November 14 From: Granite Bay, CA Member No.: 18,099 Region Association: Northern California |
Confirm that the female trigger points plug is making good contact at the distributor.
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