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Discussion Starter #1
Ok, this started about a mounth ago after I had pulled the motor to do timing belt and a new clutch.
I had very low power and the turbo was not working, turned out the map sensor was unplugged. I pluged it in and all good foe about 1 week and then started running really bad. loads of black smoke out the back. didn't want to idle that along take any throttle. had to run over 3000 rpm to clean out. low end power very bad if I could keep it running. I unplugged the MAP sensor and motor started good and had the low end power back but would not alow the turbo to work (limp mode I believe).
Car was at least driveable but very slow going to say the least. I bought a new OEM VW MAP sensor and it was fixed again. This lasted for about 10 days and is right back to no power with it pluged in. Tons of black smoke. won't idle, wont take throttle and smells like raw fuel. Unplug the MAP sensor and it will run as before with it unplugged. Am I missing something? What could be causing this MAP sensor to fail? Will the air flow sensor cause this same problem? HELP
 

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Discussion Starter #4
I am getting no codes for it.
????? I seen the MAF sensor can be bad and not through a code. Can it cause the severe rich running condition? So bad that with the MAP senson plugged in it is not driveable but with the MAP senson unplugged it is.
 

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Discussion Starter #5
I do not know if you noticed but with the MAP sensor pluged in it runs so bad it will not even idle, starts hard and will not except throttle as it loads up so badly.
No codes present
 

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Yes, the MAF sensor can be bad and not throw a code, see the MAF FAQ for some more details. Basically, there's a printed film with a sensor between 2 heater elements. The computer is pretty stupid in this regard but the MAF can show almost no airflow or some other screwy reading, as if the air filter were completely clogged or something like that. With MAF unplugged, the computer uses a default value.

Don't know why the MAP is being screwy too.
 

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Discussion Starter #8
Anyone have good luck with aftermarket MAF sensors, Are they junk and I need to stick to OEM or ok to use aftermarket?
 
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