MK 5 Throttle Body 2.0 TDI (2007)

[Fife]

Hi Everyone,

So I have the dreaded P2108 code: "Throttle Actuator Control Module Performance"

I bought a replacement throttle body from overseas and had that fitted (saved me about 75% of the price).

It drove great for 5 days, started up and switched off smoothly.. and then the engine light came back on with the same code (P2108), it also shudders now when starting and shutting off...so I get that the throttle body is not closing correctly...

I've checked the voltage on the cables and 1 -> 4 read : ~0.1V ~12V ~3.5V ~12V, anything suspicious here?

Then, if I unplug the cable while the ignition is on and then reconnect it, I can distinctively hear the motor turning and stopping... so I'm inclined to think that it's not infact the throttle body.

Anyone got any troubleshooting/helpful techniques/info?

Cheers

[panic-mechanic]

Bypass the egr and get it coded out. Orders of magnitude cheaper than trying to fix that ****

[Fife]

Bypass the egr and get it coded out. Orders of magnitude cheaper than trying to fix that ****

Do you know approximately what it would cost? And suggestions for Cape Town area to do it

Looking to sell the car soon and this is the only issue holding me back

[panic-mechanic]

Can't help in the cape. But most of thenplaces that does performace like revo and sr and those would be able to help you.

[hubbly_bubbly]

My folks 2.0TDI did the same, also replace it and was soon back. From what I could figure the plastic gears that drive the motor strip and stop opening/closing the flap accordingly (in some cases the control circuit burns out)

I will be doing as Panic described and removing the Anti Shudder Valve, ASV (proper term) as well as the Exhaust Gas Recirculation, EGR.

Its a matter of making a flange and welding a pipe of the correct diameter to accept the boost pipe. Its called a "Race Pipe" setup on a TDI because you not supposed to do it on a road car, only race cars, for legal requirements. The risk with removing the ASV is that the diesel engine can "run away" (rev up by itself) but highly unlikely.

[panic-mechanic]

You don't even have to remove the throttle body. Leave everything in place, put a blanking plate on the egr side and code it out.

[Fife]

Thank guys, I'm pretty confident now that it's not the throttle body

I just removed the pipe to take a video (below) and then I fiddled with the plug a bit - one of the pins inside is bent so may make intermittent connections or something.... plugged it back in after fiddling with it and the valve opens and closes correctly like it should - no shudder, so let's see how many days this lasts so I'm guessing it's to do with the plug connection causing the problem.

Cleared the code and nothing shows up for now...

https://youtu.be/OfWvmBInZ9I

[Fife]

So it lasted a whole 1 drive to town

I'll contact some people around here to see if they can replace the plug for me