shwndh

<center><img src="http://pictureposter.audiworld.com/44415/speed_sensor.jpg"></center><p>and they showed me this below. It's what they call an impulse sender. Does this look like what we're talking about?

diagnosticator1

Before you decide to install a new sensor, make sure the harness connector terminal contacts are clean and tight fitting on the pins. Sometimes, the contacts are damaged from test probes during diagnostic work etc. Also, you can measure the sensor resistance in Ohms, and compare to the specification. Measure both cold and hot. The sensor signal glitch is usually provoked when hot, and is not evident when cold. Considering all of the symptoms, phantom misfires, and the blinking CEL/power loss you experienced, all are consistent with a intermittent sensor signal output glitch when hot. BTW, is the 90.02 the price quoted? My ETKA shows pricing at ~$50. Maybe you could shop around if cost is an issue.

shwndh

but this dealer is always the highest in the land. I just go by there because it's close to my job. I'd like to see where the harness is located for that part so I can pull it and clean it. Also, if you know were I could buy a part like that online somewhere, please let me know. Seems like a dealer only item.

And thanx for the help.

diagnosticator1

end or the flywheel end of the engine.
Try www.genuinevwaudiparts.com, I just put that PN into the PN search there, comes back at $54.36, the online parts dept at Miramar Audi in San Diego, CA. There is also Clair Audi and Riverside Audi with online web parts stores.

Search your Bentley for "G28 Engine speed(RPM) sensor, checking". There is also reference to G28 in the Fuel Injection System, Group 13.<ul><li><a href="http://www.genuinevwaudiparts.com">Here:</a></li></ul>

shwndh

<img src="http://pictureposter.audiworld.com/44415/technical_bulletin1.jpg">

<img src="http://pictureposter.audiworld.com/44415/technical_bulletin2.jpg">

I got this from the dealer:

<img src="http://pictureposter.audiworld.com/44415/speed_sensor.jpg">

But the bulletin just says the washer needs to be removed, not replaced. The TSB does not list the 3.0 sedan but I have the exact same symptoms. Wonder why the AVK sedan is excluded. It's the same engine as the AVK cab. ?

diagnosticator1

I agree, this is most likely the cause for the problem with your phantom missfire DTCs. The TSB does include the A4, AND the cabriolet, that is implied by the comma after A4. Please post back after the spacer is removed.