L Jet issue, Fuel pump not on, injectors not firing |
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L Jet issue, Fuel pump not on, injectors not firing |
koozy |
Dec 5 2017, 01:52 PM
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#1
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Senior Member Group: Members Posts: 648 Joined: 21-July 07 Member No.: 7,931 Region Association: None |
A friend has a problem. 74 with 1.8 L Jet. Worked before removal of FI and rebuild of engine. Put the FI back on with no changes and the fuel pump won't turn on and we get no firing ofthe fuel injectors. I have no experience with L Jet. What to look at first and what fires the fuel injectors?
Thanx in advance for your help, Mike |
timothy_nd28 |
Dec 5 2017, 02:02 PM
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#2
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest |
Double check and make sure the resistor pack is plugged back in, and also check that the connector on the air flow meter is indeed on.
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timothy_nd28 |
Dec 5 2017, 02:04 PM
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#3
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest |
Also, the single white wire from the ECU needs to be plugged onto the (-) terminal of the ignition coil. The engine will not even attempt to run with that wire off.
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Dave_Darling |
Dec 5 2017, 02:32 PM
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#4
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914 Idiot Group: Members Posts: 14,984 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
If the fuel pump doesn't run, there's a good chance that nothing in the system is getting power. Check the dual relay that hangs off the battery tray.
--DD |
Mueller |
Dec 5 2017, 02:36 PM
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#5
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914 Freak! Group: Members Posts: 17,146 Joined: 4-January 03 From: Antioch, CA Member No.: 87 Region Association: None |
Quick check:
With key on you should be able to push the air flap open and the pump should turn on. |
koozy |
Dec 5 2017, 02:37 PM
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#6
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Senior Member Group: Members Posts: 648 Joined: 21-July 07 Member No.: 7,931 Region Association: None |
Fuel pump running now. No white wire coming from the ECU to the coil
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JeffBowlsby |
Dec 5 2017, 03:16 PM
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#7
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914 Wiring Harnesses Group: Members Posts: 8,501 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
The single white wire is from the FI harness.
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timothy_nd28 |
Dec 5 2017, 04:22 PM
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#8
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest |
Find and install this wire, most definitely needed! You should have 3 wires leading to the negative terminal and one wire to the positive side of the ignition coil.
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Dave_Darling |
Dec 5 2017, 06:16 PM
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#9
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914 Idiot Group: Members Posts: 14,984 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
Definitely need the single white wire connected to the coil (-) terminal. That is what tells the FI when to open the injectors!
There is also a wire in the FI wiring harness that hooks up to the T-IV connector at the right-rear of the relay board. I believe that tells the FI when the starter is cranking. --DD |
koozy |
Dec 8 2017, 06:25 AM
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#10
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Senior Member Group: Members Posts: 648 Joined: 21-July 07 Member No.: 7,931 Region Association: None |
Yep, it was the white wire. Found it, connected and fired up. Thanks, guys. I really appreciate it.
Mike |
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