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MAF Sensor in a 1999 Hyundai Elantra

I replaced the MAF sensor in my 1999 hyundai elantra. I cleared the codes after replacing and I still get the check engine light telling me the same code.

The MAF needs to be cleaned each time you replace the air filter. So does it’s connections. There is a product I’ve used for years that works well to do both.
CRC Industries makes it. I’m getting to have recommended this product enough that people are going to think I own stock. I don’t, but it works to clean up the part and connections and the code after a couple of trips.

There is no code that will tell you that the MAF is bad. There are quite a few codes that will refer to the MAF circuit. There are quite a few other codes that might have one checing or cleaning the MAF.

What is the code? And do you own a digital voltmeter? (That’s what you’ll need).

The code I am getting is P0103 which is Mass Air Flow Circuit High Input. The mechanic we had diagnose it said it needed an MAF sensor. I also borrowed a friends code reader to check myself. I will try the CRC MAF cleaner but is thier anything else I missed?

You need to check the wiring and wiring harness and verify correct voltage to the MAF. Check the whole intake tract for any kind of air leak.

I will check those items. Thank you for the advice.

I would agree with cigroller that there is no code that will tell you the MAF is bad. The codes only tell you what sensor(s) is reporting and possibly (as in this case) what it is reporting. Remember that one of the primary purposes of the OBD II is to report (to the ECU, not the FBI) that your engine is out of compliance with EPA standards. Consequently, many are “false positives”, especially where pollution compliance is at stake. That’s why your engine light comes on, even though the engine is running fine. Sometimes codes don’t clear on the first attempt and disconnecting the battery for 6-30 minutes will work (re-sets the computer). The other suggestions to check and clean the circuit and MAF seem like a good idea.

It seems like many mechanics jump to the first and most costly solution, to replace the sensor, whether it’s MAF, O2, camshaft sensor, fuel flow, etc. Kind of like killing the messenger. I think when you get to the bottom of it you should consider taking it back to the mechanic, but he will surely tell you he already threw your old one away. Good luck with it.