2007 2.5T poor throttle response

[zanzabar]

Symptoms persist, I spoke too soon. Had a longish hard stumbly start yesterday, and felt like engine was working too hard, though proportional to the gas pedal position, it was not accelerating the car like it seems it should. Felt like tranny slipping but really hard for me to say.

New throttle body seems to have livened up the engine a bit, so it's slightly better than before, but the stumbly starts and the acceleration delays seem to still be there.

[JRL]

Now a new set of plugs are in order (gapped properly)

[BrandoBob]

This sounds very similar to what I have going on, which I'm leaning towards a poohfiddled ETM, post here:
https://www.matthewsvolvosite.com/forums ... =9&t=75502

Though I get a normal gas pedal to throttle response on the tachometer, but nothing shows on the meter from the surges.

[zanzabar]

JRL I did the plugs already, only a few thousand ago, and pulled them once to try regapping which had minimal effect.

[mrbrian200]

Sure:
http://www.ebay.com/itm/331311501726

Brand: OE Replacement
Manufacturer Part Number: AWTB28075O131
Interchange Part Number: O280750131

I looked at those. I came across a blog video a month or so back where somebody decided to replace a bad stepper motor in one (a Bosch ETA of identical basic design for a Ford truck) when they took it apart the PN stamped on the motor housing traced back to a factory in China (he managed to buy a replacement motor and got his ETA working again). I ended up finding a new branded unit for $250. I actually just ordered it today. It would be interesting to tear down that white box version and compare it to a branded unit to see if they (I suspect) are exactly the same in and out with zero quality difference.

Inside mine the first few teeth on the plastic gear attached to the throttle plate were worn/binding in the part throttle range up to around 40% and not allowing the plate to return to the idle position fully. I was going around in circles for a couple months (I had multiple issues though, not just the ETA). But the ETA was responsible for poor part throttle performance, an intermittent lean condition while cruising/idling, and an occasional sputtering idle (I blamed the MAF at first). But working past the worn teeth hard acceleration /WOT was consistently as expected. Cleaning the plate would have made no difference. It wasn't dirty.

It never threw a code for the ETA until the ECM/adaptives were reset. I'm not sure if this should be considered a flaw in the ECM program or intentional (to hide major problems when at all possible past the new vehicle warranty period perhaps?)

Also, the brand new ones (Bosch# 0280750131) has an updated contactless position sensor with a circuit that emulates the older design pot sweeps signal to the ECM (back compatible, PnP). But in my case the pots on my original (0280750103) were fine. The failure was in the plastic internal gears. The contactless sensor being about 10 orders complexity over the simple pots (adding an esd sensitive microchip) likely failure rate/lifetime is about the same.