After replacing harmonic balancer vehicle will not start

2006 KIA SORENTO
100,000 MILES • 4.2L • 6 CYL • 2WD • AUTOMATIC
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MELANIE HEBERT
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  • 3 POSTS
They broke a bolt in the harmonic balancer, we got bolt out, put new harmonic balancer on. Now it will not start. It will turn over like it wants to start, but it won't start. The fuel pump is not priming itself but when you try to start it the fuel pump is pumping fuel. Please any ideas??
Oct 23, 2020 at 1:05 PM
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JACOBANDNICKOLAS
  • Experienced Mechanic
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Hi,

When this happened, was the timing belt cover removed?

What I need you to do is check for ignition spark to the plugs. I have a feeling something was missed on reassembly or the crankshaft position sensor is unplugged. That would cause loss of spark and fuel on this vehicle.

Here is a link that explains how to check for spark:

https://www.2carpros.com/articles/how-to-test-an-ignition-system

If you have a scan tool that can read live data, check to see if there is an RPM signal when cranking the engine. Also, if you haven't already, scan the computer to see if there are any diagnostic trouble codes stored in the system.

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

I also need to know if the bolt broke while the engine was running.

Let me know.

Joe.

Oct 23, 2020 at 1:42 PM
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MELANIE HEBERT
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They were trying to change the harmonic balancer when bolt broke, so I'm going to say, no the engine wasn't running. The timing belt cover was never off. I'm going to go check the crankshaft position sensor.
Oct 23, 2020 at 1:55 PM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,240 POSTS
Hi,

I attached two pics below. Note the sensor is behind the timing cover. Pic 2 shows the connection location.

If you can, check to see if there is spark to the engine.

Let me know.

Joe
Oct 23, 2020 at 2:34 PM
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MELANIE HEBERT
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  • 3 POSTS
It has spark to the engine.
Oct 23, 2020 at 4:36 PM
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JACOBANDNICKOLAS
  • Experienced Mechanic
  • 110,240 POSTS
Melanie,

You mentioned that the fuel pump isn't priming, but when trying to start, it is pumping fuel. Have you checked to see if the fuel pressure is within spec? Also, I need you to try something. See if the engine starts for a couple of seconds using starting fluid. If it does, then we know it is fuel related. If it doesn't, then we have to check the ignition again.

Here are two links. The first shows in general how to check fuel pressure. If you find there is pressure (within the manufacturer's specs) and the vehicle does start for a couple of seconds with starting fluid and then stall, I need you to check for an injector pulse. The second link explains how that is done.


https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

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

Let me know what you find. Also, let me know (if you know) what could have caused the bolt to break on the harmonic balancer.

Take care,
Joe
Oct 24, 2020 at 4:08 PM
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