Check engine soon light, code p0103

2004 BMW 325I
171,000 MILES • 2.5L • 6 CYL • 2WD • AUTOMATIC
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ARONREAMS
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My service engine soon light is on. I believe the code is p0103 for mass air flow too high. I replaced the mass airflow sensors and the vacuum hoses and cleared the code and it came back.
Nov 11, 2018 at 12:08 AM
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HARRY P
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So the most likely cause would be a short circuit or other wiring issue. The best thing to do is to get your multi-meter/voltmeter out and start probing the wires. If you do not have one, they can be bought for fifteen to twenty dollars at just about any tool shop or car parts shop, or online.

Here is the multimeter that I have: https://www.amazon.com/Craftsman-34-82141-Digital-Multimeter-Functions/dp/B000X5TSUA/ref=sr_1_3?ie=UTF8&qid=1541942173&sr=8-3&keywords=craftsman+multimeter&dpID=519%252BbqPUnoL&preST=_SX300_QL70_&dpSrc=srch

It is affordable, has about every feature that you will ever need, and has lasted me for about a decade so far.

How to use a voltmeter: https://www.2carpros.com/articles/how-to-use-a-voltmeter

How to test wiring: https://www.2carpros.com/articles/how-to-check-wiring

BMW's diagnostic information for the MAF is in the images below.

Run the tests, inspect the wiring, and let us know what you find. We will go from there.
Nov 11, 2018 at 5:11 AM
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ARONREAMS
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Thank you, and if the wiring is bad how do I go about fixing it?
Nov 11, 2018 at 12:11 PM
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ARONREAMS
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Oh and my car does a slight jerk right when I am about to stop.
Nov 11, 2018 at 12:24 PM
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HARRY P
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Small chance that slight jerk might go away with fixing the MAF issue, so let's visit that later. As for fixing your wiring, once you find the culprit, cut it out and wire in a length of wire of the same gage. Simple as that.
Nov 11, 2018 at 1:36 PM