Forget it, if the enginge run, this failure can't be for shure, before read out the codes, you should hit the starter (and let ignition on) or let the enginge run.
I'd try to clean the connectors on top of the engine, front-sided. There are two of them, a larger one and a smaller one. Disconnect them, clean them if required (they may be corroded), apply some sort of contact spray, let everything dry and reconnect it.
This is often the cause of many troubles, from "goatish" accelerations over alternativing revs to gearbox problems. It can also cause the gearbox to switch to emergency mode.
I'm in agreement with Bastian about checking and cleaning connections. The throttle pot has a wide (6pin?) connector, and is prone to water damage if the rubber boot on the connector is damaged. It's at the front of the engine. It's fairly easy to access and clean the contacts of the connector, but the unit is sealed.
The gearbox speed sensor and the O2 sensor are also able to get a bad connection due to a build up of grime. The O2 especially if there is even a small oil leak at the rear of the engine. In both case, disconnecting, cleaning off and then drying the connections afterwards may help you.
In looking for these, I discovered a loose cable hidden under my air cleaner housing (photo attached). Guess what? It plugs into the engine speed sensor (!)
This has been unplugged since before I bought the car.
The last owner sold it to as me as a parts car for the equivalent of 430 euros because every mechanic had told him his transmission needed replacing. Now that the engine speed sensor is connected properly, I have a fully functioning gearbox.
In Antwort auf: This has been unplugged since before I bought the car.
If it's true, then your car NEVER run since then? because without this enginge speed signal the engine never never never will start and you wouldn't know about transmission problems....
The one in your attachment it's the plug for the throttle... and it's not hidden under the air cleaner box - wrong attachment?
Hi Roy, it's the right attachment. I suppose its the plug for the throttle I was referring to then. It was stuffed in a void between the two rows of cylinders and just under the lip of the black plastic cover that has the Audi logo and V8 lettering on it.
The transmission has been working nicely since reconnecting whatever this is. I'm still getting some goatish revving every now and then, but that's probably another problem entirely.
I would suggest then, that the throttle pot (now reconnected) has some issues that someone tried to mask by disconnecting it.
That device gives you 3 functions. Throttle closed (idle) switch Wide open throttle (full throttle) switch And Position/angle potentiometer
A fault in mine caused erratic behaviour at 1600 rpm (I'm sure I wrote about it on this forum) Check for- Water ingress into the pot itself Bad contacts at the connector
In reply to: The matching part numbers for outer joints are: 4A0 498 099 and 4A0 498 099D
Anyhow, back onto topic for the time being; Tim, do you need both of these part numbers to assemble a complete CV joint? Or are these part numbers for the left and right front joints, respectively?
both numbers are according to the outer CV joint. You may search for both part numbers and you will find identical parts. This joints fit to RH and the LH shaft as well.
