So i've seen a fair amount of threads on this issue. There is a small DIY in the MK4 forum, but i'm getting something in our forum for the cool cats who search
Issues I experienced:
Car won't start after shutting it off for a couple minutes at full temp, have to let it cool down anywhere from 5-20 minutes.
Coming up to a stop, pushing the clutch causes the engine to die.
Slight sputtering cruising at constant speed.
Also, after this happened a few times I got my Vag-Com hooked up, but it seems like if it happens and then you get it started and it drives fine for a day there is no code, must be a quick clearing code once it sees proper operation of the sensor.
Mine was crapping out bad and was dying and un-startable at any temperature near the end and was finally able to diagnose it to the sensor with vag-com.
My 2.0 was at 214,000kms when this happened.
Quote, originally posted by Ross-Tech Wiki » 16706/P0322/000802 - Engine Speed Sensor (G28): No Signal
* Engine shuts off
* Engine doesn't start
* Speedometer inoperative
* Glow Plug Indicator Lamp (K29) flashes
* Engine Speed Sensor (G28) loose
* Engine Speed Sensor (G28) faulty
* Check Engine Speed Sensor (G28)
* The Engine Speed Sensor (G28) is also used as a reference sensor for the crankshaft position.
Part required: 06A 906 433C Engine Speed sensor or Crank Position sensor
Tools required: 1x 5mm allen key/bit OR 9 or 10mm socket (if you really can't get the bit in the hole the bolt head is close to this size) a nice flashlight and some PB Blaster or other penetrating lube of your choice.
I have found them varying in price, take your pick from an online retailer (AutohausAZ, GermanAutoParts and others carry them cheap 50-70$) I found some on ebay, but they were clearly not genuine Bosch sensors, skip that, don't need this issue coming back.
I needed a fast fix as my car was no longer operational and I got it through my parts guy in town for 115$CA and had it next day, dealership in town quoted me 150$
This is a very easy job.
Many people commented on having to remove the oil filter, I run the "BigBoy" 1.8T filter which is huge and I never had to remove it luckily, but having it off will make for easier access.
The connection is right by the dipstick, it has a gray end. Get that unplugged and follow it down, the wire sits in 2 different plastic clips one connected to the dipstick, the other to the block, open those up and get the wire out.
The sensor itself is behind and slightly to the right of the oil filter. A 5 mm hex/allen bolt is holding it in. I blasted mine with some penetrating lube, since this is a pretty high "road grime" area it's a good idea, at first I could hardly get the bit in the hole, it was filled with dirt. let that sit for a couple mins and remove the bolt.
Now comes the tricky part, once the bolt is out the sensor feels loose and will spin no problem, but for the life of me I couldn't pry it out, tried a flat head screwdriver, big pliers and so on. What I ended up doing was using one of those "useless" little small hammers you get with some tool kits, got the nail pulling end up in there and cranked it out.
I then fingered the engine block hole (haha) and cleaned out all the gunk that was sitting in there, and cleaned the outer surface with a rag and some solvent, DONT SPRAY ANY IN THE HOLE, it leads directly into your crankcase.
Now replace the sensor, it's a little tight, i used some folded up cardboard against the sensor and lightly tapped it in with that little hammer.
Replace the 5mm bolt, not too tight, don't want to crush the plastic, not sure if there is an exact torque, but it's a plastic sensor, make sure it's nicely "tight".
Replace anything you might have removed for the job, engine cover, front end under panels if you even have them.
Start the car and enjoy.