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02 plate 1.2E

Following fault codes logged. Cleared all four codes then took for a drive, P1542 re-occured first, then P1171 re-occured few miles later.

P1542 - Angle Sensor 1 for Throttle Actuator (G187): Implausible signal
P1171 - Angle Sensor 2 for " " (G188): " "

P1579 - Throttle Actuator (J338) : Adaptation Not Started
P1559 - Throttle Valve Control Part (J338) : Fault in basic settings

I'm currently thinking it needs a throttle calibration doing in VAG COM?

Also, can anybody confirm whether the throttle butterfly is supposed to remain slightly ajar or whether it's supposed to close to 90deg? I'm guessing the former, as there doesnt appear to be any other idle air supply?

I'd reckon that you are in the right area (throttle body) - so no harm in doing an adaption, I don't know without looking it up, if the pedal postion sensor gives differant codes - does it? Trying to be logical, I'd reckon that the throttle butterfly with not shut 100% as that would/could lead to jamming when the engine cooled down. Of course the throttle body mounted actuator could be faulty (just guessing).

I'd expect it to tell you some stories when you try adaption - but I think that it has already! This "adaption not started" rings bells somewhere, and on other forums has lead to people claiming that they could not run adaption - while techs have answered that this is rubbish - you should do a bit of sniffing around on the Seat (http://www.seatcupra.net) and Skoda (http://www.briskoda.net) sites for more insight as to what is what with this problem.

Have you checked up on the RossTech WiKI area for what these codes normally mean or get caused by?

RUM4MO wrote:I'd reckon that you are in the right area (throttle body) - so no harm in doing an adaption, I don't know without looking it up, if the pedal postion sensor gives differant codes - does it?

I'm presuming, (with no real hard evidence) that the first two codes relate to the pedal sensor. Could be wrong tho.

RUM4MO wrote: I'd expect it to tell you some stories when you try adaption - but I think that it has already! This "adaption not started" rings bells somewhere, and on other forums has lead to people claiming that they could not run adaption - while techs have answered that this is rubbish - you should do a bit of sniffing around on the Seat (http://www.seatcupra.net) and Skoda (http://www.briskoda.net) sites for more insight as to what is what with this problem.

Worth pointing out that these codes are from an Autel VAG405, not vag com.

RUM4MO wrote: Have you checked up on the RossTech WiKI area for what these codes normally mean or get caused by?

Not yet, I shall try and find it.

Thanks for the assist RUM4MO.

Does VAG COM 409.1 (full version) have the TBA facility under basic settings?

A licensed copy of VAG-COM 409.1 should be fully functional and throttle body adaption will not have changed much over the past 6 years, I have VCDS 805 now but up till November last year I had VAG-COM 409.1 and used it on my wife's 9N Polo 1.4 SE ( just one point, if the car has Climatronic, I'd always found that doing a complete all modules "auto scan" upsets the Climatronic so it needs read first for faults and after full scan it might need disconnecting, left for 10 minutes, reconnected and ADAPTION > BASIC settings done to it., You will know if this needs done by not being able to see it on auto scan). Back to your problem, you might now have found out that VAG-COM was created by reverse engineering, so any VAG codes or OBD11 codes will be identical to the official VAG dealer tools. I am guessing that if you can find and look into the correct area, you should see the throttle pedal input changing in a "sensible" manner - ie in a manner that you would be willing to accept as representing the pedal movement.

Once again, as I've not tried this, look into VAG-COM "uses" ie standard tasks and it should lead you into what needs done, by generally, yes, TBA should be found in engine controller> adaption>basic settings > go!

Right, have performed a TBA in the required conditions a couple of times now, and the J338 related codes seem to have gone away (touch wood).

Now only G188 and G187 re-occur as "intermittent" on a fairly regular basis, with the car often refusing to run properly, which normally clears when restarting.

Am getting a slight whistling/sucking noise as I apply the throttle just before the revs rise. Is this normal for a 1.2E or is there an air/vacuum leak?