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

asked by on July 28, 2017

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. .

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

my 1989 corvette anti lock light comes on the car will start then dies

Hi Kristine. Thanks for reaching out to us today. If you're referring to the anti-lock brake light on your Corvette, this typically does not impact the operation of the engine or would cause it to start then shut off. However,...

po598 code on bmw 335i 2007 cause

If the battery voltage is way out of range (low), yes it is possible. The complex electronic systems on modern vehicles work within narrow voltage ranges and so a faulty battery can cause malfunctions in devices that are electrically powered....

Engine temperature shows overheating

If your heater is not blowing hot air, the heater core may be clogged. The heater core is part of the cooling system loop. If coolant is not flowing into it, you will not get hot air but more importantly,...

Related articles

Industry News for Automotive Techs: October 8-14
50 MPG Chevrolet Cruz Diesel, Mazda's G-Vectoring drive system, Uber and Volvo collaborate on autonomous cars, and Hubb's new reusable oil filter.
The Best Used Cars to Buy If You’re a Wedding Planner
As As a wedding planner, the demands placed on your time are going to be significant, even if you’re only dealing with one or two couples. You need to be a master juggler when it comes to your time and...
The Best Used Cars to Buy If Your Kid's On the Soccer Team
If If you are a soccer mom (or dad), you know that you need a lot of space to transport your budding World Cup contenders, along with their gear. From time to time, you can also expect to be bringing...