Total misfire on cylinders 1, 3, 5 and 7 after engine rebuild?

TERRY V

MEMBER
2014 CHEVROLET SILVERADO
5.3L
V8
4WD
AUTOMATIC
200,000 MILES

My 2014 5.3L engine started to run bad at 200,000 miles. The active fuel management was messing up, the lifters. With that many miles I pulled the engine and rebuilt it. Rings lifters pushrods oil pump bearings (crank and cam) and installed a bigger cam. I sent the ECM and had it reprogrammed for the bigger cam, deleted the AFM, the cats were deleted. But the odd cylinders have never ‘ran’, total misfire on all four odd cylinders. The injectors have power and ground and getting fuel. Any ideas?

Monday, March 17th, 2025 AT 10:04 PM

10 Replies

KEN L

MASTER CERTIFIED MECHANIC
50,251 POSTS

Do you have good compression on those cylinders? Also, I have seen programming of the PCM go bad, which could have happened on your truck. Also, they have different crankshaft reluctor's (Tone Ring) for the crankshaft sensor, did you get a new crankshaft or did they grind yours?

24X Reluctor Wheel (Older Gen III LS Engines)

58X Reluctor Wheel (Gen IV & Later LS Engines)

Here are two guides to help:

https://www.2carpros.com/articles/how-to-test-engine-compression

and

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

How do the spark plugs look from side to side, can you upload an image? Please go over this guide and get back to us.

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Tuesday, March 18th, 2025 AT 11:30 AM

TERRY V

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6 POSTS

My truck is 2014 Gen v LTZ L 83. I used same crankshaft and piston and rods.

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Tuesday, March 18th, 2025 AT 4:26 PM

KEN L

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Okay, did you do a compression test? Also can you give me the trouble code numbers?

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Wednesday, March 19th, 2025 AT 10:25 AM

TERRY V

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6 POSTS

I did compression test on drivers' side, the cylinders that r misfiring and they look fine. Trouble codes are the P codes 0107, 018c, 0055, 0420, 0430, the C codes are 342D, 3064, 2174, 2520.

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Saturday, March 22nd, 2025 AT 12:14 AM

TERRY V

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6 POSTS

Compression test done on misfire cylinders 1, 3, 5, 7 are the same 180.

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Saturday, March 22nd, 2025 AT 12:20 AM

KEN L

MASTER CERTIFIED MECHANIC
50,251 POSTS

Are the cylinders getting spark and fuel? How does the engine seem to run can you upload short video? What do the spark plug look like, are they dark or white? Is there a chance you got the primary oxygen sensors mixed up?

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Saturday, March 22nd, 2025 AT 11:06 AM

TERRY V

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6 POSTS

Yes they are getting spark and fuel.

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Wednesday, March 26th, 2025 AT 4:20 PM

KEN L

MASTER CERTIFIED MECHANIC
50,251 POSTS

Okay, it sounds like the catalytic converter on the driver's side is clogged. This code" P0107 - Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage" is a clue.

Here is a guide to help you see what is going on:

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

You might want to loosen the head pipe to see if the engine runs better. Check out the images (below).

Image (Click to make bigger)

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Thursday, March 27th, 2025 AT 8:45 AM

TERRY V

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6 POSTS

The cats have been deleted.

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Thursday, March 27th, 2025 AT 12:06 PM

KEN L

MASTER CERTIFIED MECHANIC
50,251 POSTS

Sorry, you mention that above. I would fall back on the tune/PCM then, there is nothing else I can think of that will cause this. You have fuel, spark and compression. Did you get a chance to look at the spark plugs?

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Friday, March 28th, 2025 AT 9:24 AM