Q: p0021 Engine Light Code and trouble accellerating to faster speeds

asked by on January 14, 2018

I already asked this question , but i want to ask it again to get a second opinion on what you guys think is going on with my car. the other day i was driving along fine when all of a sudden the check engine light came on and as i went to accelerate up a hill, the engine seemed to loose power, ever since that day it has had a hard time accelerating up hills or to faster speeds. the car drives fine in the first couple gears, it only has trouble accelerating once i reach the 3rd gear or so to accelerate up hills or to go faster. i came home and hooked the car up to my laptop and it gave me code P0021, according to my research on this code, it could be a number of different things. before i start replacing all kinds of unnecessary part, what do you thing is the issue?

My car has 141745 miles.
My car has an automatic transmission.

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The underlying cause is most likely among these possibilities: 1) blocked oil passages due to sludge; 2) faulty wiring to the camshaft oil control valve; 3) a faulty camshaft oil control valve; or 4) faulty timing chain and/or camshaft phasers. Blocked oil passages and faults in the control wiring are most likely, however, in practice the way this is diagnosed is via a decision tree that is published in the factory service manual. Note, too, that loss of power although maybe partly explained by the code (P0021) can be caused by additional faults some of which will not show up as trouble codes. If you want the required diagnostic steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a a Check Engine Light diagnostic and the responding certified mechanic will investigate and resolve the issue. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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