Will not start after installing new fuel injectors?

1996 VOLVO 850
175,000 MILES • 2.3L • 5 CYL • TURBO • 2WD • AUTOMATIC
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HAMFIST
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Ran perfect into the shop. We have been chasing a MIL for misfire on cyl5 for a while, all compression 175, new plugs, new wires, new cap and rotor, new o2 sensors, new fuel pump, good pressure.

Each injector is getting 12vdc on the green wire. Found the cam position sensor connector broken, just replaced, still crank no start.

Tested injector relay on radiator shroud, tests good. All five injectors test 15ohms (spec is 10-18)

Injectors are simple, harness, connectors, remove rail, install new, reconnect fuel and connectors.

They are not spraying. They are not getting the signal to spray.

Help!

1996 850r.
Oct 19, 2022 at 11:30 AM
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STRAILER
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So, if you have one shorted fuel injector, (new defective) it will shut down the driver inside the PCM. I would unplug all fuel injectors and then see if the signal comes back, then plug them in one at a time until the signal stops, this will be the bad injector.

This guide can help as well:

https://www.2carpros.com/articles/how-to-test-a-fuel-injector

Also, we should run the codes.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please go over these guides and report back.
Oct 20, 2022 at 10:31 AM
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HAMFIST
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I cleared the codes after i replaced the injectors the first time, but they were p1310, p0303 and p0305.

Before i got your response i had also found a broken connector for the cam pos sensor and voltage tested the crank sensor (no voltage when cranking. Also, the tachometer does not move when it cranks.

I replaced the cam sensor and crank too but still no start.

I just found the plugs in cylinder 1 and 2 cracked. 3, 4, and 5 were normal.

Plug 2 was wet with fuel but no others.

I just put in new spark plugs again.

Guess i got to go rent a Noid light set.
Oct 20, 2022 at 11:07 AM
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HAMFIST
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Pulled the ECU and let it sit for 2 hours, ng, tested spark and all grounds... grounds good, but no spark.. So, some trigger somewhere isn't happening.
Oct 20, 2022 at 1:11 PM
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HAMFIST
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Just ohm tested the cpk, 277ohms, spec is 200-400. Battery 12.79vdc.
Oct 21, 2022 at 7:08 AM
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STRAILER
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Does the engine have compression? If so, let's check the overload relay in the central electrical unit. Here is the ECU wiring diagrams so You can see if it is getting power and grounds.

https://www.2carpros.com/articles/how-to-check-wiring

Check out the images (below). Please let us know what happens.
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Oct 21, 2022 at 11:50 AM
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HAMFIST
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Yes, all 5 cylinders tested dry from 165-175, I'll look into the overload now.
Oct 21, 2022 at 12:16 PM
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HAMFIST
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Checked overload relays 105, 106 and 107 and replaced with good relays, no start.

All fuses good, visually and ohm meter checked.
Oct 21, 2022 at 12:36 PM
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HAMFIST
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All three have power and ground.
Oct 21, 2022 at 12:39 PM
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STRAILER
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Does it have spark?

https://youtu.be/baq_aEWNQ0Y

Please go over this guide and report back. If so will it run on starting fluid? did you try to unplug the injectors on at a time t see if the signal comes back?
Oct 22, 2022 at 12:53 PM
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HAMFIST
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Have not tried starting fluid. I unplugged all, and started at injector #1 and went across, still no signal.
Oct 22, 2022 at 1:06 PM
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STRAILER
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Let me know if it has spark and if so will it run on starting fluid?
Oct 24, 2022 at 9:59 AM
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HAMFIST
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No spark as in an earlier reply, just checked again. Haven't sprayed starter fluid down in, because it has no spark :)
Oct 24, 2022 at 10:01 AM
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STRAILER
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Right, when you did the injectors did you remove any ground wires that are now disconnected? If you turn the key on do you have power at the positive side of the coil.

This guide can help:

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

Please go over this guide and report back.
Oct 25, 2022 at 1:40 PM
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HAMFIST
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Nope, just the 5 injector plugs. And yes, 12vdc on the coil.
Oct 25, 2022 at 1:41 PM
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STRAILER
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Did the engine run before the injector replacement? Also will it run on starting fluid?
Oct 26, 2022 at 10:19 AM
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HAMFIST
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Sadly, the owner had us take it to an older Volvo expert, I will report back.

Yes, i drove it into the shop.
Oct 26, 2022 at 10:28 AM
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STRAILER
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It sounds like one of the new injectors is shorted out stopping the injector driving inside the PCM. Please let me know what they find out.
Oct 27, 2022 at 10:02 AM
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HAMFIST
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He just called me and said he spent 3 hours on it, checking all the stuff i checked, including a new (used) ECM. No change. He will start wire pin tests Monday.
Oct 27, 2022 at 10:04 AM
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STRAILER
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Sounds good let me know, seem strange installing injectors caused this problem.
Oct 29, 2022 at 2:00 PM