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Q: Car hesitates or stalls before accelerating. Diagnostics test says: Bank 1 System too lean.

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My 2006 Accord has recently been having trouble accelerating after idling, especially after red lights. In one case, the car stalled. The check engine light goes on and off. Also, if I have the A/C on and my car is idling, my RPMs go up and down and it feels rough. A diagnostics test gave the message: Bank 1 system too lean. I know my air filter needs to be replaced, which will be done soon. My question is, is there another potential cause for this? One other thing to note: My air intake hose has been taped up with electrical tape at a previous auto service appointment. My guess is that it was torn. Could this be the problem? I've read up a bit, and some other potential issues may be a faulty fuel injector or MAF sensor.

Without having all these things looked at, which would take time and money, what would be the most likely cause for this problem?

Thank you!

My car has 130000 miles.
My car has an automatic transmission.

Hi there. Yes, a torn throttle body hose will definitely cause your concerns. Taping the boot is not a proper repair, nor will it correct the situation. The boot has to be replaced. The torn boot is allowing unmetered air into the engine and the engine computer is trying to compensate for this leak; it does not know that there is a leak, only that the O2 sensor is saying there is a lean condition. The computer will attempt to adjust anything in its power to bring the air fuel ration back to normal. This is why your check engine light is on and it has low power. Your idle air control valve is attempting to control the idle and perform a balancing act when the engine computer makes an adjustment, and vice versa: the engine computer makes an adjustment when the idle air valve makes an adjustment. This leak is also allowing unfiltered air into the engine; a bad situation that can lead to worse. I suggest having a qualified technician perform an inspection to properly confirm a diagnosis and avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a check engine light inspection.

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