Q: On slight acceleration car shakes but only when small amount of gas pedal is pressed and speed at the time don't matter

asked by on January 09, 2018

When driving at any speed when I even slightly give a small amount of gas and I mean barely even pressing it down the car will shake almost like tires are severely unbalanced but I know it's not the tires and when more gas is given the shaking goes away.. also when I have the air conditioner on or the heat on it seems to be worse the engine runs mint and I don't have no problems with the transmission so only thing I can imagine is either with spark plug issue or coil packs or maybe something with the fuel system but it's really strange that it only happens when I'm barely pressing the pedal down and goes away when more fuel was given...thanks !! And like I said it doesn't matter what the speed is at the time it does it whether I'm going 10 miles an hour or 80 miles an hour as soon as I apply only a small amount of fuel it shakes. I'm 45 years old I've been working on cars since I was 16 and I'm stumped I can usually diagnosed a problem just by the feel and sound of it but not this time

My car has 147000 miles.
My car has an automatic transmission.

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Hi Rob. Thanks for the question today. There are literally a dozen or more possible reasons why your DeVille is acting in this way. Sometimes failing wheel bearings will create the vibration you’re explaining, while in other instances, loose motor or shock mounts, a vacuum or exhaust leak or ignition timing issues can create similar conditions. As with any repair or hard to diagnose the issue, having a second set of eyes help you is typically the best way to find the problem.

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