VW passat 1997 83,000 miles

1997 VOLKSWAGEN
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DEEPSEA
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  • 1 POST
Hi Guy's,
My passat runs rough, like misfires. Two DTC codes came up. P0116 & P0131 One is Coolant temperature the other was a low voltage from the O2 sensor. I changed both sensor's with new ones and the Ignition leads just in case as the car has done 80,000mls I then cleared the codes. However, the rough running especially at low revs 1000-2000 rpm still exists. and the codes are back!! :shock:

Any idea's??? any help is much appreciated!!

Deepsea.
Aug 13, 2006 at 11:33 AM
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MRANCOU1
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For anyone reading this older original post and is experiencing a rough running engine or erratic engine speed behavior with DTC codes check your grounds first and clean them. Clean the battery terminals and all chassis ground wires (will be brown) before you do anything else. Older B4 Passats (1994-1998) all have this issue at some point and because the ECU is very sensitive to voltages throughout the individual sub-systems a sensed bad voltage will trigger certain behaviors like rough idle, engine speed suddenly dropping then increasing, you name it. You'll think your car is possesed but it's most likely a bad ground.
Sep 11, 2009 at 9:17 PM