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Q: After putting gas my engine is having a weird tapping / knock like sound ?

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I just went to go put gas (93 premium octane) into my 2007 Chevrolet Silverado vortec max. My truck was running fine prior to the fill up. When I turned it on I gave it a little gas (to2500 rpms) when I was driving off at a red light I heard a weird sound at idle. I drove home and immediately I could notice it much more noticeable . It sounds like a tapping / knocking noise , pushing it up to 1500-3000rpms and more the engine feels sluggish and doesn't want to climb . I could send a video to hear it because I can't really find a better way of explaining it and I want a solution to it as it's my baby and it hurts my heart that it's going through trouble . ( FYI I plugged in the obd2 scanner and no codes showed up for it other than an emission code but Thas because I have full exhaust with cam and more mods ) please any help is appreciated . I can even go to a shop if it's local to have it inspected in person

My car has 145000 miles.
My car has an automatic transmission.

There is a possibility that the gas is contaminated although of course the issue (the noise and the underlying mechanical cause) could have just coincidentally arose right at the time you bought gas. You might check with the station and see if they received other complaints in recent days. If there’s no issue with the gas, this problem can be diagnosed on a mobile basis, right at your location. You would just simply request an engine noise diagnostic and the responding certified mechanic will come to your location and pinpoint the origin of the noise. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you. .

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