Replaced MAF, and now CEL 0673

Hello, new member here. My problems started about two weeks ago. On my way to school I noticed the car was running very poorly, RPM's dropping by a few hundred and rising again, jerky feeling, LOTS of white smoke. On my way home that same day, i could barely keep the engine running, drove very slowly just to get somewhere safe to park. the RPM's were all over the place, an incredible amount of white smoke was coming out of the exhaust, and at anything higher than about 2000 RPM the engine wanted to die. I searched this forum and found this thread: http://forums.tdiclub.com/showthread.php?t=148753 which led me to just try disconnecting the MAF sensor to see if performance improved. Wow! All the sudden with the MAF sensor unplugged the car is back to driving around 95%. I replaced the MAF, and has been well for the last week. The only strange thing i noticed was that my glow plug light was only staying lit for about 1 second in the morning, compared to 2 or 3 seconds prior to the issues i described. It also started a little harder in these cold mornings. So this morning, it started slightly harder, and after a couple minutes of driving i got a CEL code 0673. There are many threads about the code 0673, but the timing seemed too coincidental for me. Can anyone tell me if these two issues suggest a larger problem, or if perhaps I did something while replacing the MAF sensor that might have caused damage to the glow plug or glow plug harness? I have a feeling these things are somehow connected because right after I replaced the MAF sensor i noticed the glow plug wasn't staying on as long and i was getting some harder starts. Any thoughts appreciated, thanks.

Does your car have the green coolant temp sensor?

IMO, the P0673 DTC is just a coincidence. This could be a faulty glow plug or maybe the harness just needs a shot of DeOxit contact cleaner.

Thanks for the responses.

Does your car have the green coolant temp sensor?

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This i do not know, is there any easy way to tell?

If you have a manual transmission it's a bit hard to see the CTS unless you remove the airbox. Here's an article that shows a picture:

http://www.myturbodiesel.com/wiki/t...ature-sensor-removal-replacement-mk4-vw-audi/

That's looking from the side of the left front fender.

Good work on trouble shooting the MAF. If it were me I would clear the code and see if it happens again. If it does I would pull that glow plug and test it and then replace all 4 plugs if they haven't been done for a long time. Be careful with them. They can break or strip. Good idea to soak them for a couple days with WD-40 before you pull them. As I recall the numbers on the plugs are backwards? Can anyone else verify that?

Just ohm out the GPs. I know that folks say to do some other kind of testing but this is easy enough and usually is a close enough test that it makes the most sense. I have never had this not work.