P0042 on Jetta 2006 2.5 engine check

Ginko

• 19396 Answers
• Posted on Oct 06, 2008

SOURCE: 4 Faults detected on engine diagnostics check

Try first unplugging battery cable for ten minutuse, to reset ECM, and do a scan again, there are too many unrelated error codes at the same time

SOURCE: replaced distributor in 95 jetta, now it won't start

Go back to bacic timing. put your crack shaft pully on 0 degree. Take the timing belt cover off and make sure that with the crank shaft pully is on o degree the cam shaft pully is align with a mark it has at 12:oo o'clock. If not so, turn the engine one more time using a 12 point 19mm sucket on the crank shaft till you get to 0 again. Do it very slow, it's very presice. when you align those two marks, then take the distribuitors cap off. Rotor should be pointing at cylinder 1 exactly on it. There is mark on the body of ignition to confirm this. Hope this does it. Also check if your cables are mixed up.

Steve Allison

• 5569 Answers
• Posted on Jun 27, 2009

SOURCE: 2003 Jetta TDI alternator light came on in dash

Your voltage regulator supplies the path for the control lead of the alternator and varies the amount of current available to provide the magnetic field of the armature with the required strength. Measuring from this lead to ground won't show much voltage.
Apparently the regulator is not integrated into the alternator and is probably failed. If you can chase the control lead backward, you will find the regulator and these are mostly mounted on the fender well or firewall.

SOURCE: 2004 jetta tdi, has engine miss & lack of

Running rough?? If i took a guess I'd say there's a faulty injector. Does it smoke like hell ?? Does it also miss at idle?- If so get a line wrench and a rag handy. Start the car and while idling wrap the rag around the base of the fuel line connector on injector 1 and crack it just a bit until fuel comes out. It might spray, thus the rag. If the miss gets worse, that ain't the injector to blame. Continue with the other 3. If you crack a line and there is no or very little change in the miss then you found the guilty party.

On a long shot it could also be a stuck valve.

Did that get it?? It sounds like an issue other than MAF but.... get a multimeter and try probing the connecter to the MAF. When you find out what it is , please let me know. I'm curious

*The key must be on*

pin 1- ignore it
pin 2- gnd = 12-14v
pins 2- 3 = 12-14v
pin 4- gnd = 5v
pins 3- 4 = 5v

P0101 - Mass Air Flow Sensor (G70): Implausible Signal

Possible Symptoms

• Loss of Power
• Erratic Idle

• Mass Air Flow Sensor (G70) faulty
• Air Leak(s) after Mass Air Flow Sensor (G70)
• Intake Air Filter dirty/faulty
• Ground Spots corroded or Paint Residue
• Wiring and/or Connections from/to Mass Air Flow Sensor (G70) faulty

• Check Intake Air Filter
• Check Mass Air Flow Sensor (G70)
• Check Ground Spots
• Check Wiring and/or Connections from/to Mass Air Flow Sensor (G70)

SOURCE: 97 Jetta. headlights don't work

David,
Do you have a part number or location/description of the part you replaced? I have the same problem.
John