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[cheapshots]

Hello folks,

I started my forfour this evening and it was in limp mode, very little power regardless of how much I press on the accelerator. It changed gears as normal. I switched it off, then back on and it was back to normal, however the dreaded engine management light came on.

I hooked a diagnostic tool (iCarsoft) to the OBD and found the following errors:

P0122 - M16/6 throttle valve actuator, actual value potentiometer 1 of throttle valve, voltage is too low
P01961 - actual values M16/6 (throttle valve actuator) and B28 (pressure sensor) are being checked for plausibility. Potentiometer (1)

live date stream (at idle):

battery voltage 14.08v
engine speed 750 rpm
intake pressure 28.5 Kpa
injection time 2.31 Ms
ignition angle 10 o
actuation of component Y58 (activated charcoal filter shutoff valve) 1.57%
M16/6 (throttle valve actuator) actual value potentiometer 1 of throttle valve 624 Mv
m16/6 (throttle valve actuator) actual value potentiometer 2 of throttle vavlve 4355 mV
B37 (accelerator pedal sensor) sender 1 976 Mv
B37 (accelerator pedal sensor) sender 2 956 Mv

I cleared the errors, the engine management light has gone and the car drives as normal. I'm guilty of being lazy here, I planned on cleaning the throttle valve actuator about 3 months ago but never got round to it. Am I right in saying this is step one of the remedy or am I way off?

Thanks

[Ocracoke]

Yeah, this is symptomatic of the TVA needing a clean. I'd also give the MAF sensor (the little black box next to the TVA held with a single Torx screw) a clean as well at the same time.

[cheapshots]

Thanks Ocracoke. I'll get this done during the weekend and report back here.

[Problemchild]

yeah defo TVA

JJ

[cheapshots]

Just an update - I cleaner the TVA this morning. It took me an hour in total, the hardest bit was getting access to the four torx screws!

It wasn't overly dirty, but here's hoping it fixes the issue which hasn't yet repeated itself

Thanks for your advise everybody.

[Deszus]

If cleaning anything electrical like TVA for example, keep in mind to always only use IPA to clean electrical connections. What I do between IPA is polish surfaces with very fine sand paper or steel wool.

Like new.

[CrazyG]

For those who do not understand 'technospeak' or forget
the explanation or decyphering of it 5 minutes afterwards,
just what in plain language is 'IPA' or what does stand for  ?

[Deszus]

IPA stands for Isopropyl alcohol.

[El Tel]

In my case I used dielectric contact cleaner for the contacts and carb cleaner for the throttle body itself.

I didn't remove the 4 TORX screws, I left the TVA in place while I popped out the MAP sensor and then scrubbed away with an old toothbrush inside the TVA while a mate held the throttle open from the drivers seat, followed up with a rag to get all the excess cleaner out.

It did the trick, although I am fully prepared to unscrew the TVA next time if further cleaning is needed, but since the TVA+MAP cleaning (MAP was filthy, also used dielectric cleaner for this) I have had no problems whatsoever.

I reckon (and hope) you'll have no more issues now you've cleaned yours.

[steddie eddie]

G'day Telsblay,
I did the 5 minute TVA cleaning on my forfour nearly 1.5 years ago and no problems since, so it worked for me,  hope the same for you.
Greetings,
Eddie.