I have a 94 w124 e320. I believe the throttle actuator may be bad.
Here is what the car is doing. At start up the car runs perfectly no problems. After almost exactly 3 minutes the car develops a rough engine and loss of power under acceleration. It almost feels like a car does when the Cat collapses and can't take any throttle without choking it out or you loose a cylinder on a four cyl engine. At first if I stayed on the throttle the engine would eventually clear up and accelerate as normal (typically 2 -3 seconds) at this point once the engine starts missing it will not clear up.

Additionally the car has engine surging at idle and in reverse at idle it is 200% worse
Here is what I have done.
Replaced 02 Sensor. (Ran the car for 2 weeks with the 02 unplugged before replacing and it made no difference)
Replaced MAF.
Checked and verified all coils are within specs for resistance.
Checked and verified Plug wires withing spec.
Verified the replacement of wiring harness.
Replaced OVP
I pulled the codes and got the following.

Pin 3

code 17 Data exchange malfunction between individual control module.

Pin 8

code 13 02S control system operating to rich for lean limit (replaced 02 Sens and it did nothing also drove it for a week completely unplugged and that had no effect either.)

Code 42 Can communication from ASR (I don't have ASR) EA/CC/ISC module

Pin 14

Code 9 CC/ISC Control Module

Code 5 Stoplamp switch

My question
Is there something I am missing. IS it possible that I have a sticking injector or valve sticking? What is the most likely thing to look at next? I don't want to just start replacing a bunch of $400 parts. Let me know anything you might think. Thanks

Gary

You can always open it up, and take a look-see. If you notice any bare wires, you have your answer.

__________________
It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

I found one online for $180 with warranty so I bought it. Figured It would be good to have a spare even if the one I have is not bad. I will update with what happens when i replace it. I am going to open up the old one and examine the wires and see what it looks like. If bad I will post a pic.

Wow...that's cheap. Nice find.

__________________
It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D

Yep I figured if mine was in great shape I could resell it and get back what I paid for it if not a bit more. If the one I currently have is bad I am going to swap it out and rebuild it for a spare and see how that goes.