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Engine Shaking and RPM Fluctuating While at Idle and Accelerating

Video of engine, hood (to show engine shaking), and dashboard - https://drive.google.com/file/d/1q9ZvvtOWUJqOflbIknqClnov0USEI4T9/view?usp=sharing

Hi all, please help me diagnose the issue with my 2011 Nissan Altima Coupe. Mileage - 148318. Was driving home and started accelerating from braking (red light changed to green) and then the engine started shaking the rest of the drive home with the RPM fluctuating +/- 1 of where it should be based on speed. Shaking lessened when slowly accelerating but constant at even speed and idle.

Maintenance History:

At 144738 miles

  • Throttle body fixed (had crack), PVC hose replaced with correct hose

  • Recommended but didn’t perform: Complete fuel service, Replace power steering fluid, Replace spark plugs

At 142359 miles

  • Replaced battery

  • Program ECM

  • Replaced mass airflow sensor

At 138880 miles

  • Replaced transmission

At 134949 miles

  • Replaced mass airflow sensor

  • Replaced angle sensor

  • Replaced PVC valve and PVC hose

Check the motor mounts to make sure they are tight on both sides of the mount and aren’t broken.

From your post it seems like you do not do your own work…

You didn’t say if your check engine light was on…

Why not take it into your favorite auto service place and describe the problem to them?

+1
I suspect that it is lit up, but perhaps the OP can return to clarify the matter.

No thus far I have not done my own work but with the amount of money maintenance has cost so far, I’m looking to solve this issue myself if possible. The check engine light is not on. If you watch the video linked to about 50 seconds in it shows the dashboard with the RPM fluctuating and no check engine light

Crank or cam angle sensor?

Tester

Many possibilities needs a good diagnostic workup. But my guess is a problem with unmetered air getting into engine. Check intake air path, vacuum system, and pcv system to begin

2 Likes

What specific diagnostics should I run? I have an OBD II reader so can do a variety of them from an app on my phone

The invoice doesn’t specify, it says “Product Code” is “047-200”. After looking it up online it just specifies “Tune up, Parts” for that code

Misfire and fuel trim.