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Q: Rides noticibly rough between 1500-1900 RPM (30-40mph). It feels like I'm running on bad gas.

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History: June 4th- I had my valve cover gaskets replaced. Car was fine afterwards. July 2nd- I replaced my camshaft sensor in Bank 1 (OEM part from Infiniti) after it failed while driving. Ever since, I have not been able to diagnose a roughness when driving and settling in at an approximate speed of 30-40 mph (1500-1900 rpm). Outside of those ranges, I am not noticing this roughness. It can really be felt in the pedal as I give the car gas. I do know that prior to the recent services, I never experienced this before with my car. I am the original owner. I always use appropriate 93 octane gasoline (Shell V-Power). This problem is noticed after car is warm. Any ideas? Thanks!!!

My car has 146700 miles.
My car has an automatic transmission.

Hello. A rough running condition that occurs only at a certain rpm can be hard to diagnose. I would start by double checking the mounting of the cam sensor that you installed as well as the electrical connector. If either are not evenly seated then this will occur.

If those are fine then I would typically scan the computer for any codes related to the roughness and check the fuel trim readings. It sounds like it may be as simple as a tune-up. If this has not been done in some time I usually pull a few of the spark plugs to see if they are fine. I would also do this just to make sure that no oil is getting on the coil boots.

If this is somethings that you want to have looked at, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your rough running condition. Best of luck.

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