Q: Car Codes p300 through p306 go off and code p1406

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Car Codes p300 through p306 go off and code p1406. Also car does shake at certain speeds; one day it will shake when I am going around 20-30mph and other times it will start shaking at around 60-70mph. If the car is on, but parked it emits a heavy burned gas smell. I have taken it to a few different mechanics and none of them were able to fix the direct issue. They have been able to alleviate some issues though to be honest with you. So far what has been done, changed the oxygen sensor twice, rebuilt the transmission, replaced ignition coils, I have changed the gas cap, and still it has the blinking engine light on. Last mechanic said it could be EGR valve, but the bolt is stripped and I cannot get it out with my home tools. I do not want to sound overly exaggerated, but please tell me you can help out without having to pay an arm and a leg again to attempt to fix it.

My car has 228000 miles.
My car has an automatic transmission.

Hi There, Code P1406 relates to the EGR valve as you may know. The EGR valve is a small component designed to allow the flow of exhaust gases into the intake manifold in controlled amounts. Whenever you start the engine, the valve comes activates and waits in a closed position, blocking the flow of exhaust gases. Once the engine reaches operating temperature and speed increases, the valve, either through vacuum or electronic control will gradually open, allowing burned exhaust gases to enter and combine with the air-fuel mixture inside the combustion chamber. When the EGR valve is clogged or dirty, as they are prone to, it may not function properly causing the engine to idle rough, stall at idle speeds, cause the car to get poor fuel mileage, or emit a strong smell of fuel due to excess hydrocarbons which also results in failing emissions tests. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle to properly diagnose and repair.

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