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Q: Intake air flow leaking. What makes this happen?

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changed motor oil. started car, check engine light stayed on. went to auto zone got p0171 code. disconnected positive battery cable. r and r maf sensor. removed one month old air filter, blew out with air. blew out air filter compartment with air. installed air filter. connected battery cable. started car. check engine light stayed off. went to store one mile away. locked car with remote. came out of store half hour later, tried to remote start car. would not. said oh crap. started car with key and engine light stayed on. went to auto zone checked for codes and was told car had an air flow intake leak. double checked r and r ing air filter. saw not problems. checked hoses and connections and saw no problems. did not disconnect battery when r and r air filter for the last time. engine light still on. help sam. thanks. .

My car has 55200 miles.
My car has an automatic transmission.

Hi there. When having the code P0171, the fuel system is too lean. This could be the fuel pump is not working, the fuel filter is dirty or plugged, or the injectors are plugged or not working properly. Check the fuel system and make sure that the fuel system is having a pressure of 35 psi or higher. Also, check the spark plugs and look for any burn marks. This would indicate that the spark is hotter than normal and the fuel system needs cleaned or repaired.

For the intake air flow leak, check the intake for any vacuum leaks on both sides of the throttle. Check all of the hoses from the air cleaner box to the throttle and check the manifold and all vacuum line including the brake booster line for any leaks. Put a vacuum hose on the engine and see what the engine vacuum is at idle. The vacuum should be 17 hg to 22 hg on the gauge. If there is a vacuum less that that, then there is a leak. If you need further assistance with your fuel system and a vacuum leak, then seek out a professional, such as one from Your Mechanic, to help you.

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