Q: P2178 and P115D codes are showing up on a scanner. Could both be related to the MAF sensor?

asked by on November 29, 2016

Could both be related to the MAF sensor? Runs rough for about 30 seconds after start when cold then smooths out and runs fine. Recent head job, and timing chain, guides and tensioner work done but was doing this before hand. The HPFP is about a year old and I was pretty careful with the connectors and vacuum connections. It is a heavily modified engine. Just about every bolt on upgrade you can imagine and Manic stage 2 tune.

My car has 153000 miles.
My car has a manual transmission.

Mass Airflow Sensor Replacement $188.36 - $786.53 Get a Quote
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Hi there. The code P115D is for the mass air flow sensor (MAF). It says that the sensor has an offset signal. The code P2178 says that bank 1 is too rich. This means that the engine is running too rich (has too much fuel or not enough spark). Check the spark plugs to see if they are working and if they are soaked in fuel. Also, check the fuel pressure regulator to see that its functioning. I recommend performing a fuel injection flush first to make sure that there is no contaminants in the fuel rail. Also, I recommend replacing the MAF sensor for its not sending a correct signal to the computer, as if it has a broken connector or a short. If you need further assistance with the codes that you are getting on the code reader, then seek out a professional, such as one from Your Mechanic, to help you.

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