Q: Hey I got this BMW I got code p0491,p0492,p0455

asked by on February 23, 2017

The car barley idles with out wanting to shut off and and makes a occasional grinding sound from the engine How can fix this issue I checked most of the Hoses but I can't seem to figure it out

My car has 177000 miles.
My car has an automatic transmission.

Check Engine Light is on Inspection $94.99 - $114.99 Get a Quote

Hello. The grinding sound occurring on your vehicle is likely caused by the secondary air pump failing internally. I believe so because the codes in your vehicle P0491 and P0492 are both codes related to the secondary air injection system. When the air pumps fail they tend to produce a grinding noise. The last Code P0455 is an EVAP emission code stating that there is a leak detected in your system. The leak could be from an EVAP line, evap canister, or maybe a faulty gas cap. I suggest that you have a technician such as one from YourMechanic evaluate your vehicle to help further advise you on how to fix it. You are able to find a technician and book an appointment here https://www.yourmechanic.com/services/check-engine-light-is-on-inspection

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