Q: Rough idle, dip in idle, no acceleration power, replaced cam postion senor, cleaned pistons, spark plugs, and vvt what else?

asked by on February 22, 2018

The car idles rough, dips in idle, poor acceleration, and shakes. We have replaced the cam postion sensor, the fuel pressure regulator, the vvt, cleaned the throttle body, changed the spark plugs, changed the fuel filter, and cleaned the pistons. What else could it be.

My car has 268000 miles.
My car has an automatic transmission.

You should have the computer scanned for misfire codes to see if one or more cylinders are misfiring and may have a bad coil or plug wire boot. Also check for vacuum leaks in the intake gaskets since any of this can cause rough idle and misfire. An EGR valve code may also be present if valve is stuck in the open position. Additional diagnosis can be done by a mechanic like one from YourMechanic to assist you with further diagnosis.

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