Hesitating/knocking

196,688 MILES • 5.0L • V8 • 2WD • AUTOMATIC
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KOREYCASLIN
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My truck listed above is the xlt model. It’s my first vehicle and I am 16. I started experiencing problems with the truck like hesitation once i push on the gas to pull out in front of somebody. Or even trying to pick up speed. After hesitation it slurs and has very exaggerated stutters while being put into acceleration. Rarely will it ever knock, and by that I mean it actually sounds like somebody is hitting the chassis with a sledge hammer over and over. It will also smell like burnt oil within the cab. I have replaced the belt and O2 sensor (knowing this has nothing to do with it), did a tune up, replaced both catalytic converters, and checked it with the “check engine” light on. Please help. I’ve taken it to 3 mechanics and neither know what’s wrong.
Dec 1, 2019 at 6:16 AM
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ASEMASTER6371
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Good afternoon,

Did you test the fuel pressure? Low fuel pressure would do this issue.

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

Ignition timing would also be something you need to check. If the timing is retarded, it will hesitate.

The knock does not sound good. That may be a warning sound that the engine is going to fail at some point. Go easy on it if you want it to last.

https://www.2carpros.com/articles/engine-noises

Roy
Apr 6, 2021 at 5:46 AM
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KOREYCASLIN
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Fuel pressure was checked and good, but by a backyard mechanic. since there are 2 fuel pumps (one in the engine itself) i’ll have to ask if both were checked. and ignition timing i will check that. thank you. and are there any possible reasons leading to the engine knocking ? anything i can fix?
Apr 6, 2021 at 5:46 AM
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ASEMASTER6371
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I would need to hear it before I can give you a idea of the noise.

What was the pressure?

Do you have a carburetor or is it fuel injection?

Roy
Apr 6, 2021 at 5:46 AM
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KOREYCASLIN
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it sounds like something is trying to turn but is getting caught, and then pushes through, causing a hollow knock. and it’s fuel injected.
Apr 6, 2021 at 5:46 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Okay. You do not have a fuel pump on the engine. That is only for carburetor models.

Roy
Apr 6, 2021 at 5:46 AM
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